aktivnosti v preteklem letu (maj 2009 - maj 2010) 14 ... · 12. kolokvij o asfaltih in bitumnih ......

Maj 2010, leto XIII.

Aktivnosti v preteklem letu (maj 2009 - maj 2010)14. redni letni zbor članov ZAS12. kolokvij o asfaltih in bitumnihIzobraževanje asfalterskega kadraProizvodnja asfaltnih zmesi v letu 2009Intervju s predsednico uprave DARS, Matejo Duhovnik Strokovni prispevki

14.

n Društvu strokovnjakov za področje asfaltov! ___________________ 3

n 14. redni letni zbor članov ZAS ______________________________ 4

n Strokovni posvet: Ponovna uporaba asfalta - recikliranje __________ 5

n 12. kolokvij o asfaltih in bitumnih ___________________________ 6

n 7. izobraževanje tehničnega asfalterskega kadra ________________ 9

n Izobraževanje IZS:»Projektiranje, naročanje in nadziranje asfalterskih del« _________ 10

n Proizvodnja in vgrajevanje asfaltnih zmesi v letu 2009 __________ 11

n Sodelovanje z ostalimi združenji (EAPA, Gestrata, DRC, ...) _______ 12

n Delovanje organov ZAS v letu 2009 _________________________ 13

n Intervju s predsednico uprave DARS, Matejo Duhovnik ___________16

n Strokovni prispevki______________________________________ 24- Voziščne konstrukcije na avtocestah in v predorih –

asfalt ali beton? Slovenko Henigman _______________________ 24- Gumirane asfaltne zmesi, Bojana Lukač _____________________ 28

n From assembly to Assembly in English _______________________ 33

n Asfalterske novičke _____________________________________ 45

n Nekatere objave o ZAS-u__________________________________ 46

n Program dela za leto 2010 ________________________________ 47

2 od skupščine do Skupščine

OD SKUPŠČINE DO SKUPŠČINE

Iz vsebine

Glasilo »Od skupščine do skupščine« izdaja ZAS, Združenje asfalterjev Slovenije Kotnikova ul. 32, 1000 Ljubljana

Uredila:Slovenko HenigmanBranka Čulič

Prevod: Domen Kavčič

Fotografija na naslovnici:Dejan Simčič

Foto: Arhiv ZAS, Dejan Simčič

Oblikovanje: Robert MihelčičGrafična priprava: RM design d.o.o.Tisk: Rotosi d.o.o.Naklada: 1.000 izvodov

ISSN 1408-6166

3od skupščine do Skupščine

UVOD

Vztrajanje na povezovanju, učinko vi -tem organiziranju in nenehnem razvo -ju slovenske cestne stroke je imperativčasa, še posebej v zaostrenih pogojihgospodarjenja na področju gradbe -ništva in v povezanih dejavnostih. Iz -ko ristiti moramo ta čas za pripravopotreb nih osnov za prihajajoče ob dob -je živahnejših naložbenih aktiv nosti,zato je kreiranje strokovnih usme ritevin priprava podlag za spre jemanje ka -ko vostnih odločitev na loga vseh stro -kovnjakov, ki so povezani z razvo jem inohranjanjem prometnic. In to je tudiprednostna naloga vseh združenj, ki seukvarjajo s proble ma tiko načrto vanja,upravljanja, gradnje in vzdrže vanjacest in drugih pro metnic.Izobraževanje in informiranje je v civil -nem Združenju asfalterjev Slove nijedeležno osrednje pozornosti že odusta novitve tega zelo uspešnega dru -štva, saj se je bilo le tako mogoče prib -ližati zastavljenim ciljem delova nja, toje težnji za kakovostnejšimi in traj nej -šimi asfaltnimi produkti, traj nostnimraz vojem tehnologij in večje mu zado -voljstvu uporabnikov cest. Rezultatidol go letnih prizadevanj so opazni nacestah, pri uvedbah najso dob nejših po -stop kov dela in pri uporabi kakovostnihmaterialov, ki po membno prispevajo kvečji gospo dar nosti naložb.Združenje asfalterjev je doseglo zavid -ljiv ugled doma in v mednarodnem pro -storu. Vzpodbuja povezovanje z osta li -mi društvi s področja cest in prometakot tudi v okviru Družbe za raziskave vcestni in prometni stroki Slovenije. Žalneargumentirane, po splo šene, populi -stične in lažne ocene stroke na splošnoter gradbeništva, v medijih in politiki,ne upravičeno zma nj šujejo dosežene uspe -

he na področju razvoja gradbene stro -ke. Temu se bo treba v prihodnje še od -loč neje postaviti po robu z doku men ti -ranjem našega dela in s korekt nim terpopolnim obveščanjem najširše jav no sti.Naslednja velika priložnost za ude ja -njenje rečenega bo jubilejni 10. slo -ven ski kongres o cestah in prometu, kibo oktobra v Portorožu. Združenjeasfal terjev Slovenije je soorganizatortega velikega srečanja domačih in tujih

strokovnjakov. Za taizziv in delo v pri -hodnje želim društvučim več uspehov.

Matija VilharDirektor družbe DRC

V Sloveniji je bilo v zadnjih desetletjih vokviru inženirske oziroma cesto grad -bene stroke ustanovljenih kar nekajneprofitnih civilnih združenj, ki naj biorganizirala, povezovala, promoviralain skrbela za razvoj stroke na tempodročju. Če jih na kratko naštejem:Društva za ceste v Ljubljani, Mariboru, vNovem Mestu in Društvo za cestePrimorske, DRC-Družba za raziskave vcestni in prometni stroki Slovenije,ZAS-Združenje asfalterjev Slovenije intudi Nacionalni komite PIARC Slove nija.Ustanovitvam teh združenj je botrovaltudi sorazmerno hiter razvoj in gradnja(avto)cestnega omrežja v Sloveniji.Nacionalni komite PIARC Slovenija jebil ustanovljen v letu 1999 kot GIZ –gospodarsko interesno združenje, kizdružuje preko 30 organizacij, ki delu -jejo na področju cestogradnje, odmini strstev, upravljalcev cest, razisko -

val nih inštitutov in gospodarskih družb.Nacionalni komite deluje v okviru sve -tovnega cestnega združenja (WRA)PIARC, ki ima sedež v Parizu. V PIARC jevčlanjenih preko 100 držav sveta,številne med njimi so ustanovile tudinacionalne komiteje. Slovenski nacio -nalni komite PIARC opravlja šte vilnenaloge na področju cesto grad be nestroke, med drugim organizira deloslovenskih strokovnjakov v tehničnihodborih PIARC-a, (so)organizira različ -ne prireditve in dogodke kot so sejetehničnih odborov, okrogle mize, work -shope in konference.V mesecu aprilu letos sem bil na skup -ščini združenja NK PIARC izvoljen zapred sednika Upravnega odbora s 4 let -nim mandatom. Mnenja sem, da mo ra -mo slovenski inženirji v času, ko se zak -ljučuje ciklus velikih investicij pri iz -grad nji cestnoprometne infrastruk turev Sloveniji in se skuša le na podlagieksces nih dejanj nekaterih posamez -nikov v celoti razvrednotiti in kri mina -lizirati delo številnih stro kov njakov prinačrtovanju in izgradnji slovenskih(avto)cest, tudi v okviru vseh naštetihstrokovnih združenj strni ti moči inargumentirano zavrniti neupravičenekritike ter pokazati slo ven ski javnosti,da je stroka svoje delo opravila dobro,korektno, pošteno in v slovenskemnacionalnem interesu. Sam se bomzavzemal in aktivno deloval v tej smeri.

Vili Žavrlan Predsednik UO NK PIARC Slovenia

Translation from page 33 ...

Društvu strokovnjakov za področje asfaltov!

Upravni in nadzorni odbor ZASNa zadnjem Zboru članov je bil izvoljentudi nov Upravni odbor ZAS, ki šteje 11članov. V Upravni odbor so bili izvolje -ni najbolj aktivni člani in predstavnikivseh 9. podjetij, ki delujejo v I. rangusodelovanja z ZAS. Zaradi odhoda izdružbe CPM d.d. je iz UO ZAS odstopilnjihov predstavnik g. Matjaž Mernik.Na njegovo mesto je bil izvoljen pred -

Redni letni zbor članov ZAS je potekal14. maja 2009 v Dolenjskih Toplicah.Prisotnih je bilo 63 članov združenja.

Poročilo o delu ZAS za leto 2008Poročilo o delu združenja v letu 2008 jepodal predsednik ZAS Slovenko Henig -man. V preteklem letu si je ZAS zadalonaloge, ki so bile postavljene na 13.zboru članov na Bledu in so po izho -dišču podobne vsa leta delovanja.Društvo skrbi za prenos znanj in pretokinformacij, zagotavlja nadgradnjo teh -nične regulative, omogoča pove zo -vanje akterjev v asfalterski industriji indrugo. Za zagotavljanje takšnih dejav -nosti pa mora skrbeti tudi za ustreznoorganiziranost in sredstva za delovanjedruštva. Za navedeno organizira ZASvsako leto večje število strokovnihsrečanj in dogodkov, katerih vsebina jebila predstavljena v tradicionalnembiltenu, ki ga letno prejmejo vsi članiZAS. V letu 2008 je ZAS organiziralonaslednja srečanja:

• strokovni posvet na zelo aktualnotemo Smernice in tehnični pogoji zavgradnjo asfaltnih plasti,

• kot novost je bila organizirana je -sen ska delavnica na temo dimen zio -niranja, katere so se v določenem

številu udeležili tudi projektanti.Cilji so bili predvsem vzpodbuditiboljšo izdelavo elaboratov in

• konec novembra 2. Dan asfalterjev.

Sledila so poročila vodij tehničnegaod bo ra (TO) in Odbora za zdravje,varstvo in okolje (OZVO).

Kratko poročilo o delu tehničnega od -bora TO v preteklem obdobju je podalvodja g. Janez Prosen. Glede na zelointenzivno leto so se sestali na trehsestankih. Delo je bilo osredotočenona izdajo in pojasnila izvirnih slo -venskih standardov SIST 1038. Pred -stavil je tudi nekaj pobud predvsem zavzpodbudo reciklaže in nizkotem pe ra -turnih asfaltov, obravnavo in vključe -vanje v razširjene preiskave in potrebopo vpeljavi nove merilne in tehnološkeopreme.

Osnovne aktivnosti OZVO, ki se pred -vsem navezujejo na aktivnosti odboraHSE pri EAPA je podal g. AleksanderKerstein. Izpostavil je potrebo za pri -pravo novelacije knjižice Asfalti invarstvo okolja z varovanjem delavcev.Gre za delo skupine strokovnjakov, kijih je zaradi preobremenjenosti težkouskladiti, tako da se bo v prihodnostipotrebno odločiti ali bo knjižica boljinformativne narave ali bo služila kotpripomoček. Zaradi vedno več enakihvprašanj in tematik, ki jih obravnavataTO in OZVO – je po vzoru EAPA pozdravilskupne sestanke.

Kot zaključek poročila o delu združenjav lanskem letu, je g. Henigman pred -stavil še nekaj iztočnic, po katerih sibomo zapomnili zadnje leto 2008:

• pričetek novega mandata vodstvaZAS;

• rekordna proizvodnja asfaltnih zme -si v Sloveniji 2008;

• vgradnja 1 mio ton asfaltov za naj -težje prometne obremenitve (od -prto skoraj 100 km AC);

• nezadržna rast prometnih obre -menitev;

• uvedba novih standardov SIST EN13108 in SIST 1038 in pripravaSmernic;

• izdaja publikacij s strani ZAS.

Na osnovi navedenega je ocenil, da jeZAS v celoti opravil zadane naloge, za -to se je vsem članom tudi zahvalil zaopravljeno delo in zboru članov pred -lagal, da sprejmejo poročilo o delu, karje bilo z aplavzom tudi soglasnopotrjeno.


LETNI ZBOR ČLANOV ZAS

14. redni letni zbor članov ZAS


STROKOVNI POSVET

stavnik iz družbe CPM d.d., g. VasjaGrmek.

Z letošnjim zborom članov se je iztekeltudi mandat nadzornemu odboru ZAS vsestavi Marijan Makovec, predsednik,Janez Prosen in Miro Žnidaršič, člana.Glede na njihovo uspešno delo, jim jezbor članov mandat podaljšal do leta2012.

Pozdravni nagovoriUdeležencem Zbora članov je spre go -voril župan Dolenjskih Toplic, g. FrancVovk. Izrazil je ponos, da smo za svojesrečanje izbrali prav Dolenjske Toplicein še posebej pozdravil našega pred -sednika, ki je rojen »Topličan«. Čestitalje za uspešno delo v preteklosti inzaželel veliko uspešnih aktivnosti vprihodnje.

Občinstvu je spregovoril tudi g. MatijaVilhar, izvršni direktor za tehničnopodročje in gonilna sila DRC d.o.o., kije okarakteriziral ZAS kot steber stro -kovnih aktivnosti v gradbeni stro ki.Med drugim v času ekonomske ingospodarske krize vidi priložnost doka -zovanja tudi na področju želez niškeinfrastrukture, kjer se čuti pri manjkljajustreznega kadra. Na koncu je vseprisotne povabil na jubilejni 10. kon -gres o cestah, ki bo naslednje leto vPortorožu in se pridružil čestitkam zaopravljeno delo.

Kot zadnji je zboru članov spregovorilg. Žavrlan, direktor za področje razvojaprojektov pri DDC svetovanje inže -niring. Tudi on se je dotaknil »recesije«in opaža, da se zmanjšujejo investicijev Sloveniji. Kljub rekordni proizvodnjiasfaltnih zmesi v letu 2008 je samo 30% asfaltnih zmesi vgrajenih na avto -cestah, kar mu vliva optimizma. Prepri -čan je, da ZAS zelo dobro obvladujesvoje področje in da bo še naprej delalouspešno.

Pomen ponovne uporabe rezkanca (zrezkanjem odstranjenega starega as -fal ta), ki sta ga na posvetu predstavilag. Janez Zupan iz CP Ljubljana in ing.Franz Fegelin iz Asfinag-a, pridobivana pomenu. Razvite države (Nizo zem -ska, Nemčija, idr.) v novem asfaltuupo rabljajo tudi do 80 % starega asfal -ta. V Sloveniji to tehnologijo obvla du -

jemo, se pa predvsem zaradi manj šihkoličin rezkanca manj upo rablja. Vprihodnje bo zaradi večjih vgrajenihdebelin in zaradi racio nali za cije terzniževanja stroškov ta tehno logija pri -dobivala na pomenu. Proiz va jalci asfal -tov pričakujejo ustrezno podporo inosveščenost tudi s strani naročnikov,saj je potrebno delo ustrez no razpisati.

Strokovni posvet:Ponovna uporabaasfalta - recikliranje

Letni zbor se je zaključil s kulturnimprogram

Kolokvij o asfaltih in bitumnih je naj -večje mednarodno strokovno sreča njeasfalterjev, ki ga bienalno organi ziraZAS. Že tradicionalno je potekal konecnovembra (26. in 27. novembra 2009) vHotelu Kompas v Kranjski Gori podglavnim pokroviteljstvom energet skedružbe Petrol in ostalimi devetimipokrovitelji, ki so se prijazno odzvalipo va bilu k sponzoriranju kolokvija.Leto recesije se je pokazalo tudi prištevilu udeležencev, predvsem smopogrešali udeležence iz Hrvaške inSrbije, ki so se udeleževali prejšnjihdveh kolokvijev. Kljub temu pa smo

zabeležili 192 udeležencev od tega 22iz tujine. Predstavljenih je bilo 19 stro -kovnih prispevkov in 20 razstav ljalcev.

Pred 12. kolokvijem o asfaltih in bitum -nih so bila organizirana srečanja stro -kov nih odborov ZAS, tradicionalno paje bil organiziran tudi sestanek Odborapodjetij in družb, ki združuje vse pred -stavnike včlanjenih podjetij. Pri sotnihje bilo 50 aktivnih članov ZAS. Polegrednih tem in pregleda do gajanja ZASje bila organizirana tudi internaokrogla miza z gostoma pred sednikomEAPA, g. Egbertom Beuvin gom in direk -

torjem GESTRATA g. Maxom Weixl bau -mom, s katerima smo izme njali sta -lišča na vnaprej priprav ljene teme.Ugo tovitve okrogle mize kažejo na po -dobna vprašanja, tako v Sloveniji,Avstriji kot Evropi.

Prvi dan 12. kolokvija o asfaltih inbitum nih, ki ga je z uvodnimi besedamiotvoril predsednik ZAS, g. Henigman,je spregovoril tudi župan občine Kranj -ska Gora, g. Jure Žerjav in direktorZavoda za gradbeništvo dr. AndražLegat. V nadaljevanju smo poleg stro -kovnih prezentacij v dveh sekcijah


12. KOLOKVIJ O ASFALTIH IN BITUMNIH

12. kolokvijo asfaltih in bitumnih



• Razvoj tehnoloških postopkov(moderator: Zvonko Cotič) MarjanMarolt, Dr. Jochen Holzfeind, Prof.Dr. Johann Litzka, Zvonko Cotič,

• Predstavitev Evropskega projektaSPENS(moderator: Mojca Ravnikar Turk)Mojca Ravnikar Turk, Julijana Jam -nik, mag. Mihael Ramšak, dr. Sta -nislav Lenart, dr. Marjan Tušar

organizirali tehnične predstavitve terodmevno okroglo mizo »Kako z veli -kimi državnimi naložbami v promet -no infra strukturo v Sloveniji v pri -hod nje«. Vodilni predstavniki naro -čnikov, inže nirja in izvajalca kontroleso skušali odgovoriti na vprašanja: »Boglobalna kriza in recesija zares ustavilapred videne velike infrastrukturne pro -jekte? Kje bo država našla prepotrebendenar za cestno in železniško infra -strukturo? Kako bo preživela slovenskagradbena industrija?« Eminentnemuskupu je uvodoma spregovoril državnisekretar dr. Igor Jakomin, ki je meddrugim opo zoril tudi na pomen Slo -venije kot pomorske države z LukoKoper in morjem kot oknom v svet.

Mateja Duhovnik,predsednica upra ve DARS d.d.

mag. Gregor Ficko, direktor Direk cije R Slovenije za ceste

dr. Andrej Godec, direktorDirekcije R Slovenije zavodenje investicij v javnoželezniško infrastrukturo

mag. Zmago Skobir, direktor Aero droma Ljubljana

Ljubo Žnidar, glavni direktor DDCsvetovanje inženiring

dr. Andraž Legat, direktor Zavoda zagradbeništvo

Moderator: Jože Bonča, novinar

Za zaokrožitev malce napornega, apoučnega dne nas je za piko na ipozdravila Manca Izmajlova s svojimžametnim glasom in pozvala prvegaslavnostnega govorca, predsednikaZdruženja asfalterjev Slovenije, g.Slovenka Henigmana. V nadaljevanjusta vse prisotne pozdravila tudi pred -sednik uprave Petrol, g. Aleksan derSvetelšek in član uprave Petrol, g.Roman Dobnikar. Oba sta bila mnenja,da sta ZAS in Petrol z leti zgradilačvrsto partnerstvo, dosegla velikoskup nih ciljev in s tem spodbujatanapredek na področju asfalterstva. Zazaključek slavnostnih govorov je spre -govoril še dr. Peter Gašperšič, v.d. gen.direktorja Direktorata za ceste.

Odmevna okrogla miza »Kako z velikimi državnimi naložbami v prometnoinfra strukturo v Sloveniji v prihodnje?«, ki jo je vodil Jože Bonča

Kolokvij je nagovoril dr. Igor Jakomin,državni sekretar na MP

Zdru ženje asfalterjev Slovenije je tudina letošnjem kolokviju podelilo pri -znanja najbolj zaslužnim posa mez -nikom. Prejela sta jih dva izjemnastrokovnjaka. Prvi je priznanje za svojedelo in pomoč pri razvoju slovenskeasfalterske stroke prejel g. JanezZupan, ki je prišel – očitno že s fakul -tete »zastrupljen« s hlapi bitumna – vprvo službo na zavod za raziskavomateriala in konstrukcij, v Oddelek zaceste in izolacije. Po 15. letih je odšel kizvajalcu Cestno podjetje Ljubljana,kjer je do danes vodja laboratorija.Asfalterski stroki ostaja zvest že vsodelovno dobo. Strokovna znanja, ki jihje osvajal in oddajal, so bila vedno na -menjena predvsem zagotavljanju kako -vosti asfalterskih del. Kot eden

vodilnih in upoštevanih asfalterjev prinas, je poleg reševanja vsakodnevnihopravil pri proizvodnji in kontroli kva li -te te predstavljal tudi most med slo ven -skimi in nemškimi asfalterji. Bil je re -den gost številnih nemških stro kov nja -kov in strokovnih srečanj. Znan je tudikot velik pristaš tradicije in praktič -nosti.

Njegovi največji dosežki so predvsemprva uvedba• asfaltne zmesi SMA in• uporaba rezkanca v asfaltni zmesi v

Sloveniji.

V svoji karieri je pripravil veliko številostrokovnih mnenj in znanstvenih član -kov, večkrat je aktivno sodeloval naZAS-ovih srečanjih.

Drugo priznanje je za pomembenprispevek k razvoju asfalterske stroke vSloveniji prejel g. Feliks Podgoršek.

Feliks Podgoršek je kmalu po zaposlitvinašel delovno mesto, ki mu je bilo »pi -sano na kožo«. Skoraj tri desetletja jebil v podjetju SCT med vodilnimi delavcipri proizvodnji in vgrajevanju bitu mini -ziranih zmesi. Ves ta čas je v asfalterskipraksi uspešno uveljavljal nova stro kov -na spoznanja. Rezultati tega dela so ševidni. Feliks Podgoršek je velik pozna -valec obratov in pro izvodnje as falt nihzmesi, zato mu ni bilo težko po potrebitudi samostojno izvajati proizvodnjo aliodpraviti poma njklji vosti v delovanju.Svoja znanja pa kljub upokojitvi, vpodjetju ›DDC sve to vanje inženiring‹,koristno posreduje še danes.

V zrelih letih svoje kariere je bil pojemugotavljanja vzrokov za nastale po -škodbe, imel je izjemen občutek zauvajanje novih tehnoloških postopkov.Bil je en redkih Slovencev, ki je pri deluv arabskem svetu osvojil preprostibesednjak, s katerim je šarmiral in ob -vla doval nadzornike.

V zadnjih letih je zaslužen, da so as -falterski popisi del dobili na pomenu inkvaliteti.

Drugi dan kolokvija smo nadaljevali sstrokovnimi prispevki, ki smo jih zdru -žili v dve sekciji

• Tehnična regulativa in modernelaboratorijske preiskave (mode ra -tor: Egbert Beuving)(Aleksander Ljubič, dr. ZdravkoRamljak, dr. Markus Spiegl, mag.Bojana Lukač, dr. Janez Žmavc)

• Varstvo okolja v asfalterstvu(moderator: Zvonimir Britovšek)(dr. Andreja Zupančič Valant, KlausGraf, Egbert Beuving, ZvonimirBritovšek, mag. Dejan Hribar)

in sprejeli tudi zaključke 12. kolokvija oasfaltih in bitumnih:• Nova tehnična regulativa, ki smo jo

uspešno vpeljali skupaj s certifi -ciranjem nam omogoča sigurno instabilno proizvodnjo, vemo kaj jepotrebno narediti, da bo asfaltustrezno vgrajen (TSC).

• Uspešno so bile vpeljane labora -torijske preiskave pri visokih innizkih temperaturah, v naslednjemobdobju je treba vpeljati še dodatnedinamične preiskave preverjanjatogosti in utrujanja.

• Sprejeta je nova regulativa zadimenzioniranje, ki pa še ni bilapod vržena preveritvi, zato predla -ga mo, da vpeljemo prehodno ob -dob je za končno uveljavitev !

• Uporaba alternativnih materialov(žlin dra, guma, apno itd.) in ponov -na uporaba asfalta z rezkan cem sonaša prihodnost. Pogoj za uporabo jezagotoviti enako kako vost pro duk ta,kot če delamo z »novimi« ma te riali.

• Manj hrupne vozne površine so našaobveznost, na tem področju so po -treb ne izboljšave in koraki na prej.Podobno je stanje pri nizko tem pe ra -tur nih asfaltih, kjer ugotav ljamozastoj v razvoju.

• Potrebne so izboljšave izdelave pro -jektov in popisov ter javnih nateča -jev za delo na voziščnih konstruk ci -jah, zato je potrebno omogočiti pro -jektantom, da pridejo do dodat nihznanj. Predlaga se organiziranje de -lav nic, pri čemer bomo skušali vklju -čiti tudi IZS. Razmišljamo o predloguza vpeljavo licenc za izdelavo projek -tov za dimenzio niranje voziščnihkonstrukcij. Od daja del po sistemu»najnižje cene« ne daje vednonajboljših rezultatov. Pripraviti jetreba predloge za bolj učinkovite ininovativne načine oddaje del.

• Potrebno je vzpostaviti redno komu -nikacijo z naročniki in fakultetami.Zakaj pri nas ne poznamo inženirjaza voziščne konstrukcije (PavementEngineer)? Kako bi vzpodbudili šo -la nje za ta poklic?

• Nadaljevati se mora razvoj obratov,mehanizacije, ponovno je trebavzpod buditi uporabo dodajalca zaasfalt Shutle Bugy.



Pozdravni nagovor g. Svetelška,predsednika uprave Petrol innajvečjega pokrovitelja

Janez Zupan in Feliks Podgoršek s priznanji


IZOBRAŽEVANJE ASFALTERSKEGA KADRA

Letošnje izobraževanje operativnegaasfalterskega kadra je potekalo 3.marca 2010 v Hotelu Mons ter asfaltnihobratih Smodinovec in Črnuče v Ljub -ljani. Program izobraževanja je bilrazdeljen na teoretični in praktični delter zasnovan tako, da so bila obrav -navana vsa bistvena področja vasfalterstvu namenjena operativnemuasfalterskemu kadru.

V prvem teoretičnem delu je bila obrav -navana splošna tematika – posebejpomembna za operativni tehnični ka -der – od proizvodnje do vgrajevanjaasfaltnih zmesi. V tem segmentu je g.Janez Zupan udeležence seznanil zrazličnimi vrstami in posebnostmi as -falt nih obratov, označevanjem as falt -nih zmesi ter proizvodnjo asfaltnihzmesi s poudarkom na ponovni uporabi

asfaltnih zmesi – rezkanca. G. MarjanMarolt je povzel cilje in pomen dobreorganizacije ter planiranja asfalterskihdel, od katerih je odvisna kakovostizvedenih del. Pomen dobre pripravedelovišča v prometnih zaporah terpriprave podlage za asfaltiranje jeobravnaval g. Sebastjan Černigoj.Pregled posameznih delovnih procesovod asfaltiranja do zgoščevanja asfalt -nih zmesi ter povzetek najpogostejšihnapak pri omenjenih procesih pa jenazorno prikazal g. Igor Grahek. V pri -spevku g. Janija Planinca je bil podanpregled postopkov popravil in posa -meznih tehnologij, primernih za dolo -čen namen uporabe pri sanacijah ob -sto ječih cest, ki zahtevajo resen instro koven pristop, tako pri dolo če va -nju vzrokov poškodb, kot tudi pri odlo -čitvah o vrstah sanacije.

V zaključnem prispevku prvega dela jepredsednik združenja g. Slovenko He -nig man prisotne seznanil z zaključkiIARC-ove študije, ki je obravnavalaškod ljivost bitumenskih hlapov nazdra v je delavcev v asfalterski industrijiter povzel stališča in zaključke 12.kolokvija o asfaltih in bitumnih. S svo -jim nastopom je pojasnil avditoriju, dabitumenski hlapi in aerosoli po ugoto -

vitvah številnih mednarodnih študij nevplivajo škodljivo na zdravje ljudi.Sledil je predstavitveni film sanacijeletališke steze na Letališču JožetaPučnika na Brniku, ki je bila izvedenaleta 2009.

Praktični del izobraževanja je bil raz -deljen na štiri segmente. Udele ženci sobili razdeljeni v manjše skupine, ki sokrožile. Na praktičnem poligonu naSmodinovcu so bili pod vodstvom g.Janeza Šuštarja pred stavljeni delovnipostopki pri vgraje vanju asfaltnih zme -si in nastavitve finišerja ter nivelirnihnaprav. G. Marko Balkovec je predstavilposamezne na sta vitve in delovanjevaljarja ter postop ke pri zgoščevanjuasfaltnih zmesi.

7. izobraževanje operativnegaasfalterskega kadra

Janez Zupan

Jani Planinc

Priprava vzorcev

Meritev z izotopsko sondo

Inženirska zbornica Slovenije je napobudo ZAS-a organizirala izobra že va -nje za vse projektante, naročnike innadzornike, da se bolj podrobno spoz -najo z novimi tehnologijami na pod -ročju asfalterstva, z novimi stan dar di,ki so izšli v letu 2008, vključno z novimioznačbami asfaltnih zmesi in z novimipopisi za projektiranje in naročanjeasfalterskih del.

Predstavljena so bila naslednja preda -vanja:• Evropski in slovenski nacionalni

stan dardi za asfalte (AleksanderLjubič)

• Začetni preskus in kontrola pro iz -vodnje v obratu (Aleksander Ljubič),

• Smernice in tehnični pogoji zagraditev asfaltnih plasti (ZvonkoCotič) in

• Praktični primeri (Zvonko Cotič).

Izobraževanje je potekalo 27. januarja2010 v prostorih IZS v Ljubljani. Prijav -ljenih je bilo 55 udeležencev.


IZOBRAŽEVANJE ASFALTERSKEGA KADRA

Izobraževanje IZS:

»Projektiranje,naročanje in nadziranjeasfalterskih del«

Drugi del je potekal na področju asfalt -nega obrata Črnuče, kjer je bil podvodstvom g. Boštjana Tušarja pred stav -ljen asfaltni obrat in posamezne fazedela na asfaltnem obratu pri pro -izvodnji asfaltnih zmesi. S strani g.Romana Bašlja je bila predstavljenatekoča kontrola omenjenega pro izvod -nega obrata ter posamezni postop kimeritev, ki jih izvaja notranja oziromazunanja kontrola, tako pri proizvodnji,kot tudi pri vgrajevanju asfaltnih zme -si, bitumnov in zmesi kamnitih zrn.

Izobraževanja se je skupaj udeležiloveč kot 130 udeležencev iz 24. cesto -gradbenih podjetij, ki aktivno sodelu -jejo z ZAS. Vsi udeleženci so prejelodelovno gradivo s povzetki predavanjin letni bilten združenja ter na koncutudi potrdila o zaključenem izobra že -vanju.

Udeleženci izobraževanja so prejeli tu -di anketni list, katerega so na koncuoddali. Analiza kaže da so bile temeletoš njega izobraževanja za sodelujočikrog aktualne, potrebne in dobro iz -bra ne, čeprav bomo sprejeli tudi pred -log, da bi za operativni nivo, izo bra -ževanje potekalo bolj v obliki razprave,manj v podajanju prosojnic. Za uspešnoizvedbo izobraževanja gre iskrenazahvala vsem predavateljem in članomorganizacijskega odbora ter podjetjuSCT Asfalti d.o.o., ki je omo gočilo prak -tični del izobraževanja na svojih strojihin lokacijah podjetja.

mag. Jožica Cezar

Roman Bašelj

Boštjan Tušar

Aleksander Ljubič


PROIZVODNJA ASFALTNIH ZMESI

V letu 2009 smo v Sloveniji proizvedli2,3 mio ton vročih asfaltnih zmesi.

Za proizvedene asfaltne zmesi je biloporabljenih približno 1,8 mio tonkarbonatnih in 400.000 ton silikatnihzmesi kamnitih zrn in 85.000 tonbitumenskih veziv. Od tega je bilovgrajenih 70.000 ton cestogradbenihbitumnov in dobrih 15.000 ton spolimeri modificiranih bitumnov. Deležmodificiranih bitumnov glede na pora -bo vseh bitumnov je v letu 2009 znašal18 %.

V letu 2009 je bilo med ostalimi asfaltiv Sloveniji proizvedenih in vgrajenih143.000 ton SMA, 136.000 ton AC bin,714.000 ton AC surf in 1.300.000 tonAC base, delež drenažnih asfaltnihzme si pa je znašal 5.200 ton.

Proizvodnja in vgrajevanjeasfaltnih zmesi v letu 2009

CP Kranj

SCT CPM

ZAS je član EAPA že od leta 1997. Našipredstavniki so vključeni v vsa telesaEAPA (Odbor direktorjev, Tehnični od -bor, Odbor za zdravje, varstvo in oko -lje), preko katerih se zagotavlja pre nosinformacij v domače okolje.

Med avstrijskim in slovenskim zdru že -njem asfalterjev smo v zadnjih 15. letihvzpostavili odlično sodelovanje. Polegmedsebojne udeležbe na naših sreča -njih in drugih aktivnostih pote kajo tuditradicionalni obiski vodilnih predstav -nikov naročnikov in izvajalcev bodisi vAvstriji ali Sloveniji. V tem času smozabeležili preko 300 medsebojnih iz -me njav. Po tradiciji je na vrsti ponovniobisk slovenske delegacije na Dunaju,ki jo bomo skušali organizirati v začet -ku julija 2010.

Z nemškimi kolegi (DAV) se srečujemopredvsem na naših največjih srečanjih

v Kranjski Gori in Bertesgadnu. Tako jebilo tudi letos, ko je bilo kar nekajčlanov DAV na 12. kolokviju o asfaltihin bitumnih ter tudi naša skupina naXV. nemških asfalterskih dnevih. Odlič -no organizirani asfalterski dnevi sonakazali kakšen prispevek lahko dajoceste pri reševanju gospodarske krize.Nemčija namerava poleg znatnihsredstev za obnove (do 2 % vrednostiinvesticij letno) v obdobju do leta 2015kar 50 mrd EUR nameniti za investicijev 1900 km novih avtocest in 2200 km vrazširitve obstoječih.

Velik poudarek dajejo tudi skrajšanjuobnov, zato so pripravili poseben»Bauzeitkatalog«, katerega uporab -nost bomo skušali preveriti tudi nanašem omrežju. Aktivnosti v to smer žepotekajo.

10. SLOVENSKI KONGRES O CESTAH IN PROMETU 21. do 23. oktober 2010

Jubilejni 10. Slovenski kongres o ce -stah in prometu bo potekal od 21. do23. oktobra 2010 v Grand hoteluBernardin v Portorožu.

Organizacijski odbor bo izdal zbornikstrokovnih referatov in zgoščenko(CD). Posebej za to priložnost pa bo -do izšle tudi tri knjige, Vzdrževanjecest, Zgodovina cest – ceste na Slo -ven skem in Kako smo gradili avto -ceste.

Pomembni datumi:23. december 2009Vabilo avtorjem za pripravoreferatov

31. marec 2010Prijava referatov, predložitevosnutkov povzetkov

1. julij 2010Predložitev celotnih tekstovreferatov v končni obliki

10. september 2010Program in vabilo za udeležbo nakongresu

9. oktober 2010Zgodnji rok za prijavo udeležbe –nižja kotizacija

18. oktober 2010Skrajni rok za prijavo udeležbe –višja kotizacija

20. oktober 2010Program kongresa – 3. obvestilo


SODELOVANJE

Sodelovanje z ostalimizdruženji (EAPA, Gestrata, DRC, ...)

Nemški minister za promet dr. Peter Ramsauer


DELOVANJE ORGANOV ZAS

Upravni odbor (UO)Od zadnje redne skupščine, je biloorganiziranih šest sej, ki so bile vsesklepčne, saj je bila na sejah doseženaokoli 80 % udeležba članov. Sprejetihje bilo 42 sklepov, ki so bili v celotirealizirani. Poleg 11. članov UO ZAS so se sejUpravnega odbora redno udeleževalitudi predsednik NO g. Marijan Makovec,vodja TO g. Janez Prosen, ga. JožicaCezar in g. Zvone Cotič.

UO je gonilo delo va - nja združenja, saj sena njegovih sejahob delajo vsa naj po -memb nejša organi -zacijska in stro kov -na vpra šanja.

Tehnični odbor(TO)Aktivnosti tehnič -ne ga odbora ZAS vdaljšem časovnemob dobju kažejo, dase sledi aktualni te -matiki tehnične re -gu lative in pred -pisom na evrop -

skem in slovenskem pod ročju. V letu2009 je bilo delo ve zano na imple -mentacijo že izdanih izvirnih sloven -skih standardov SIST serije 1038, pote -kale so razprave o ustrez nosti vsebine,še bolj pa o izbra nih kate gorijah last -nosti. Pobude so spro vedene, doku -menti so odprti za nad gradnjo, teh -nični odbor pa je v po ve zavi z aktual -nimi spoznanji v praksi, tehnično regu -lativo obravnaval tudi z vidika sklepovoperativnih sestankov komisije zaasfalt.

Delo tehničnega odbora ZAS je zajeloobravnavo in spodbudo po obvlado va -nju postopka certificiranja na obratihza proizvodnjo asfalta, po Evropskidirektivi o gradbenih proizvodih CPD.Ti postopki so se vpeljali dokaj tekoče,čemur je botrovala velika aktivnosttehničnega odbora s sestanki pred -stav nikov proizvajalcev asfalta in in -ten ziven dialog s kontrolnimi službami.

Zelo pomembno je, da je delo tehnič -nega odbora botrovalo visoki stopnjiobvladovanja preiskav kontrole ka -kovo sti, saj je znaten poudarek namedlaboratorijskih preiskavah. V letu2009 je sprovedena konstruktivnakritična obravnava glede obvladovanjalast nosti tako vhodnih materialov, kotsamih proizvedenih zmesi invgrajevanja. Vodilo dela odbora jebilo, kako obvladujemo kakovost. Primaterialih, še posebno bitumenskihvezivih, je dana pobuda po razširjenihpre iskavah, določitvi temperaturnegarazpona ve ziv, ki jih uporabljamo(PG).

Izpostavljen je bil trajnostni vidikstanja vozišč. Dana je spodbuda zaobvladovanje funkcionalnih lastnostiasfaltnih zmesi in plasti, kar pomeni,da je aktualna tema dela tehničnegaodbora tudi obravnava tako imeno -vanih razširjenih preiskav, ki smo jihpoimenovali »dinamične preiskave«.

Evropa je usmerjena v ohranjanjeresur sov in varovanje okolja. V ospred -je prihajajo zahteve iz tako imenovanihokoljevarstvenih direktiv, ki vedno boljnarekujejo uporabo obstoječih virov.Asfalt kot material za reciklažo. To se vtehničnem odboru intenzivno obrav -nava in spodbuja. Tema je bila pred -stavljena s prezen tacijami v sklopu lan -skega zbora članov preko članovtehničnega odbora.

Tehnični odbor je v svojem delu v 2009obravnaval tudi nizkotemperaturneasfalte, povzel informacije iz preteklihlet in dal spodbude za delo v pri -hodnje.

Delovanje organov ZASv letu 2009

Organigram organov ZAS

Člani UO ZAS na asfaltnem obratu TAPv Murski Soboti

Delo tehničnega odbora je sledilovsebini in poudarkom obravnav tehnič -nega odbora Evropskega združenjaAsfalterjev TC EAPA, ki interese napodročju asfalta povezuje in promovirav EU. To so že omenjeni vidik trajnosti,ohranjanje virov, varstvo pri delu invarstvo okolja, s posebnim povdarkomna sodelovanju TO ZAS in odbora ZVOZAS. EAPA preko TC pripravlja vrstodokumentov v cilju promoviranja, razu -mevanja, osveščanja in spodbu janja zaasfalt, ki je najbolj razširjen gradbenimaterial v cestni infrastruk turi nasvetu. Spodbuda v TC EAPA je pripravadokumenta o reciklaži na področjubitu menskih materialov, podob no kotje že izdan dokument reciklaž na pod -roč ju betona. To je tudi vsebina aktiv -nosti tehničnega odbora v ZAS-u intema sestankov v bodoče.

Iz razprav, ki so bile tema dveh glavnihsestankov v juniju in novembru 2009 jerazvidno, da je delo tehničnega odboraZAS usmerjeno v pomoč kontrolnimsluž bam, proizvajalcem asfalta, in -vesti torjem in nadzornim službam terizvajalcev. Je način sistematične izme -njave mnenj, vidna je moč povezovanjain osveščanja.

Skozi delo tehničnega odbora so daneinformacije o dogajanjih na tehničnemin operativnem področju doma in vtujini, dane spodbude za informacijepreko portala ZAS. Vidi se, da gledetehnične razvitosti v ničemer ne za -osta jamo za razvitimi državami v svetu.

Tehnični odbor ZAS je v letu 2009obravnaval in s pobudami nakazal smernačrtne spremljave asfalta kot mate -riala zgornjega ustroja vozišč. Širi po -bu do, ki jo je začel leto poprej, daasfalt mora biti vse bolj poznan gledebistvenih lastnosti tudi načrtovalcemoziroma projektantom voziščnih kon -struk cij.

Zaključimo lahko, da so bile aktivnostitehničnega odbora ZAS v letu 2009sistematične s ciljem celovite infor ma -cije za krepitev znanja s tehničnegapod ročja asfalta. Vsem sodelujočim prinašem delu se lepo zahvaljujem inspodbujam povezovalno delo tudi vnaprej.

Janez Prosen

Odbor za zdravje, varstvo,okolje (OZVO)Usmeritve delovanja:Zdravje delavcev-varstvo pri delu delav -cev v proizvodnji, vgrajevanju-pola ga -nju asfaltnih zmesi, izvajanju izolacij inpri drugih delih z bitu menskimi pro -izvodi. Posebna pozor nost je usmer jenav varovanje delav cev, ki izvajajo dela obprometu in varovanje ostalih ude le -žencev v prometu.

Varovanje okolja je opredeljeno napreprečevanje oziroma zmanjševanjeobremenjevanja okolja pri proizvodnji,vgrajevanju in celovito pri delu z bi -tumenskimi proizvodi. Te usmeritve seizvajajo z zmanjševanjem emisij v zrak,vodo in tla, razpršenih emisij in imisij.

Enako pomembno je zmanjševanjeproduciranja CO2 in emisije v okolje.Poudarek je dan tudi zmanjševanjuporabe energije in uporabi obnovljivihvirov energije.

V obdobju 2009/2010 se je odborsestal dvakrat v novembru 2009 inmaju 2010.

Na obeh sestankih so se obravnavaleteme po naslednjih točkah kot sledi:• Informacije o projektih za varovanje

okolja, ki se izvajajo v EU in zade -vajo tudi asfaltersko dejavnost

• Informacije o poteku projekta REACH(obvladovanje uporabe, pre vozovkemikalij)

• IARC študija-zaključki• Dogovor o novem načinu delovanja

odbora s ciljem večje aktivnosti insodelovanja vseh članov odbora zdoločitvijo nosilcev tem-članov od -bora, ki planirano ali zaradi aktual -nosti svojo temo predstavijo naodboru s priporočilom, da se pred -hod no uporabi spletna komuni ka -cija z ostalimi člani odbora

• Recikliranje (hladno in vroče) asfal -tov z vidika varovanja okolja indelav cev v delovnem okolju (izpo -stava delavcev izparinam iz asfalt -nih zmesi).

• Nizko temperaturni asfalti: predčasom aktualna tema v asfalterskidejavnosti je sedaj nekako v ozadju.Cilji po zmanjšanju porabe energijein zmanjševanje izparin gotovo vo -dijo preko nizko temperaturnih as -fal tov. Ugotovitve IARC študije sozmanjšale potrebo po nizkotempe -raturnih asfaltih, ki so dražji, raz li -

ko v ceni pa naročniki niso priprav -ljeni prevzeti. Uporaba je trenutnoomejena predvsem na liti asfalt.

• Obravnava izvedenih pristopov vasfaltnih obratih v Sloveniji po 7.členu Uredbe o emisijah iz naprav zaproizvodnjo asfaltnih zmesi.

• Informacije o novih tehnologijah:npr. uporaba gumiranih asfaltov zupo rabo gumiranih bitumnov. Tatehno logija ima prihodnost polegteh nič nih in okoljskih karakteristik,po sebej še z vidika varstva okolja napod ročju zmanjševanja hrupa zaradipro meta. To je sedaj zelo aktualnatema v EU.

• Na obeh sestankih so bile podanetudi informacije o aktualnih aktiv -nostih v EAPA.

Aleksander Kerstein

Sekcija za hidroizolacije (SHI)Člani Sekcije za hidroizolacije so se včasu od zadnjega rednega zbora članovZAS srečali na enem sestanku.

Zaključena je bila krožna preiskava bi -tu menskih lepilnih mas, v kateri jesodelovalo pet laboratorijev, ki sopreiskovali lepilne mase treh proizva -jalcev in laboratorij Tehnične UniverzeGraz, ki je še dodatno izvedel meritvepotisne trdnosti. Rezultate primerjalneanalize bomo člani sekcije podrobnoanalizirali na prihodnji seji.

Poudarki iz programa dela za leto 2010 so:• obravnava lastnosti materialov in

postopkov za horizontalne hidro izo -lacije objektov

• spremljanje razvoja zakonodaje napodročjih bitumenskih materialov

• skrb za promocijo znanja med upo -rabniki.

Kolegom iz sekcije in vsem, ki njenodelo podpirajo, se iskreno zahvaljujemza prizadevanje in pomoč in upam nauspešno sodelovanje tudi vnaprej.

Olga Naglič

Sekcija za izobraževanje (SI)Izobraževanje asfalterskega kadra jenajpomembnejša naloga združenja, kijo koordinira Sekcija za izobraževanje.Programi izobraževanj se glede naaktualno tematiko pripravljajo za teko -če leto sproti. Osnutek programa okaterem se razpravlja je pripravljen žev mesecu novembru preteklega leta inpredstavljen na Sestanku Odbora pod -jetij in družb, ki je običajno v sklopu





Kolok vija o bitumnih oziroma Dnevaasfalterjev.

Vsako leto se izmenično organiziraizobraževanje tehničnega in usposab -ljanje operativnega asfalterskega kad -ra. Ciljne skupine za posamezno izo bra -ževanje niso striktno ločene to po meni,da se nemalo inženirjev udele žuje tudiizobraževanja operativnega kadra, karje seveda z njihovega sta lišča zelopraktično, za nas pa vzpod bud no, saj topomeni, da ohranjamo ni vo primeren zaceloten asfalterski kader.

Pri organizaciji izobraževanj se zave da -mo pomembnosti praktičnih prikazov,zato izobraževanje delimo na teore tič -ni in praktični del, kjer dobijo udele -žen ci priložnosti, da izpostavijo svojeprobleme, izmenjujejo mnenja in iz -kuš nje.

Izobraževanja tehničnega asfalter skegakadra so običajno organizirana cen -tralno v Ljubljani, prav tako pa je biloletos prvič v Ljubljani organizirano tudiizobraževanje in praktično uspo sab -ljanja operativnega kadra (na po ligonu,asfaltni bazi in laboratoriju, v manjšihdelov nih skupinah), kar je podrobnoopisano v poglavju Izobra ževanje.

Pri izbiri tematike izobraževanj se pri -lagajamo potrebam in trenutnim raz - meram v asfalterstvu. Udeležence sku - šamo sproti seznanjati z novostmi napodročju tehnične regulative, labo ra -torijskih preiskav in laboratorijskeopre me, pri proizvodnji in vgrajevanjuter zgoščevanju asfaltnih zmesi, teh -no loškimi postopki sanacij … pa tudivar stvu delavcev in varovanju okoljaposvečamo veliko pozornosti. Poleg iz -vedbe vsakoletnih izobraževanj sode -lujemo pri pripravi strokovnih srečanjin ostalih aktivnosti ter po potrebiorganiziramo okrogle mize, delavnicein seminarje. Povabljeni pre davateljiso navadno strokovnjaki iz naše as -falterske sredine, aktivni člani naše gazdruženja, ki sodelujejo tudi pri pri -pravi gradiva.

Sekcija za izobraževanje se v celotni se -sta vi vsako leto sestane na enem šir šemdelovnem sestanku, kjer pri pravi izho -dišča za odločitve upravnega od bo ra.Orga nizacijski odbor sekcije za pripravokonkretnega izobraževanja se skupaj spredavatelji v času orga niza cije izo -braževanj sestaja večkrat po potrebi.

Za kakovostno delo SI je izrednegapomena, da pri izbiri potrebnih tematiksodelujete vsi udeleženi v tem procesu.Vaše pobude, mnenja in pripravljenostna sodelovanje so pri tem zelo dobro -došla. Potrudili se bomo, da bomo tudiv prihodnje izpolnili vaša pričakovanja.

Prav tako si želimo povratnih infor ma -cij o zadovoljstvu udeležencev, zatovse, ki se udeležite naših izobraževanjpro simo za izpolnitev ankete.

Vsem članom SI se ob tej priložnostizahvaljujem za sodelovanje in si želimdobrega sodelovanja tudi v prihodnje.

mag. Jožica Cezar

Komisija za asfalt (KZA)Preteklo leto je KZA aktivno sodelovalapri pripravi Smernic za vgrajevanjeasfaltnih zmesi, katere je oblikoval inkoordiniral prof. dr. Janez Žmavc. Po12-ih dopolnitvah in uskladitvah sobile smernice z naslovom: TSC 06.300/06.410 SMERNICE IN TEHNIČNI POGOJIZA GRADITEV ASFALTNIH PLASTI objav -ljene v Uradnem listu Republike Slo -venije, št. 65, dne 14.8.2009.

TSC 06.300/06.410 je tehnična speci -fikacija za javne ceste z neobveznouporabo, vendar kot obvezni sestavnidel razpisnih pogojev za gradnjo invzdrževanje cest v Republiki Sloveniji.Dokument poleg vgrajevanja pokrivatudi projektiranje, saj so sestavni delSmernic tudi popisi.

KZA se je v letu 2009 sestala na trehsestankih in sprejela vrsto sklepov.Poleg Smernic se je komisija aktivnoukvarjala s problematiko uporabe Črnejeklarske žlindre za izdelavo obrabnozapornih asfaltnih plasti za najtežjeprometne obremenitve, ter z dodaja -njem asfaltnega agregata (rezkanca) vbituminizirane zmesi za zgornje nosil -ne asfaltne plasti za najtežje prometneobremenitve. Komisija je podprla iz -ved bo poskusnega polja za žlindro insoglašala z uporabo rezkanca v spodnjinosilni plasti AC 32 base, tudi za cesteobremenjene z izredno težko prometnoobremenitvijo. Žal naročnik ni soglašals takšno uporabo, kar je predvsemposledica premajhne informiranosti omožnostih uporabe starega asfalta vnovem.

V ta namen smo v septembru orga -nizirali strokovno izmenjavo s kolegi izavstrijske avtocestne družbe Asfinag vGrazu. S slovenske strani so se obiskaudeležili predstavniki DARS, DDC, ZAG,Igmat, Primorje in se lahko prepričali ouporabi tega asfalta na avtocestah vsosednji Avstriji.

Obiska se je udeležil tudi Andrej Vovk,univ. dipl. inž. grad, vodja službe zaorganizacijo obnov pri DARS, ki je takokot običajno s svojimi pronicljivimistro kov nimi idejami, vprašanji inmnenji doprinesel k uspešnosti obiska.Andre ja od 31. januarja 2010 žal ni večmed nami, kar je zelo velika izguba zaslovensko cestarijo, ki ji je posvetilvelik del svoje kariere. Kot človeka instrokovnjaka Andreja neizmerno po -gre šamo.

Komisija za asfalt je strokovno teloDARS, ki je bilo ustanovljeno leta 1995.V 15-ih letih delovanja je komisija, kise je sestala na 74. sejah doživelavzpone in padce. Čas in naloge nare -kujejo razširitev delovanja KZA tudi napodročje državnih cest, saj so izzivi zadelo KZA v prihodnje:• zmanjšanje hrupa,• povečanje udobja voznih površin,• povečana trajnost voznih površin in vse to ob nenehnem povečevanjupro metnih obremenitev.

Slovenko Henigman

Nadzorni odbor (NO)Nadzorni odbor v sestavi: predsednikMarijan Makovec in člana, Janez Prosenin Miro Žnidaršič se je sestal 7. aprila2010, neposredno pred zadnjo sejoUpravnega odbora. Pregledali so fi -nanč no in računovodsko doku men -tacijo in podali pozitivno mnenje napregledani zaključni račun za leto2009, ki ga bo sprejemal letošnji zborčlanov ZAS.

Andrej Vovk


INTERVJU: MATEJA DUHOVNIK, PREDSEDNICA UPRAVE DARS D.D.

Intervju z Matejo Duhovnik



Mineva 15 let kar intenzivno gradimoavtoceste. V tem času je bilo uspešnodokončanih za Slovenijo impozantnih450 km avtocest. Poleg številnihobjektov, viaduktov in predorov jebilo uspešno izvedene tudi 900 kmdvo ali tropasovnih smernih vozišč -nih konstrukcij. Te so v največji meriasfaltne, v kombinaciji s cementnostabilizacijo. V času intenzivne grad -nje je bilo po podatkih ZAS na avto -ceste vgrajenih okoli 5 – 6 mio tonasfaltnih zmesi.Kako je z izgradnjo avtocest v prihod -nje in kako si v DARS-u predstavljajozagotavljanje ustreznega vzdrže va -nja, so iztočnica za pogovor s pred -sed nico uprave, go. Matejo Duhovnik.

Ga. Duhovnik, na čelu DARS-a steprib ližno 6 mesecev, kar vam žeomogoča pogled na prehojeno pot.Kako ocenjujete teh prvih 6 mesecevna tej funkciji?

Prve korake kot predsednici upraveDARS d.d. mi je precej olajšalo dejstvo,da sem družbo relativno dobro poz -nala, saj sem bila v letih 1994-1998 ter2001-2003 članica nadzornega svetadružbe DARS, ravno tako pa sem bilačlanica nadzornega sveta tudi pol letapred imenovanjem na mesto pred -sednice uprave. Res pa je, da sem šele ste pozicije spoznala vse razsežnostidelovanja naše družbe in s tem sevedatudi vrsto vsakodnevnih problemov inizzivov. Sama težko ocenjujem svojedelo v tega prvega pol leta, sem pa vse -kakor ponosna na nekatere premike, kismo jih skupaj s sodelavci uspeli dosečiv tem obdobju. Takoj v prvih mesecih,ko sem nastopila mandat, smo uspeliprekiniti »začarani krog zapletov« prioddaji del na predoru Markovec in šepred iztekom lanskega leta končnopodpisati pogodbo z izbranim izva -jalcem. Ravno tako nam je uspelo pri -dobiti manjkajoči zemljišči za grad njozadnjih dveh odsekov avtoceste mi moTrebnjega, predčasno smo do kon čalitudi z deli na priključnih ceveh predoraŠentvid. Ob mojem prihodu v družbo jebilo nezasedenih tudi nekaj ključnihkadrovskih pozicij, ki smo jih v temčasu v glavnem ravno tako uspeli za -pol niti, kar pomeni dobro osnovo zanadaljnje delo. Seveda daje mojemude lu pečat tudi trenutna gospodarskakriza, ko se srečujemo z zahtevamiizva jalcev po predčasnih plačilih, pri -

tiski podizvajalcev, ki jih njihovi po -god beni partnerji ne poplačujejo, kljubtemu, da imajo s strani DARS d.d. kotnaročnika vse obveznosti poravnane.Ponosna sem tudi na svoje sodelavce,ki jim je skupaj z zunanjimi izvajalciuspelo v rekordno kratkem času ponov -no omogočiti promet skozi trojanskepredore le nekaj dni po požaru v pre -doru Trojane. Z letošnjim letom smozačeli z diferenciranim cestninjenjemtvornih vozil glede na evro-emisijskeraz rede, kar je bil za družbo še posebenizziv ob upoštevanju, da obstoječi cest -ninski sistem ni bil načrtovan za takšennačin cestninjenja. Zavedam se, da jedružba v prelomnem obdobju, ko se bo -mo morali preoblikovati v pravegakoncesionarja, ko končujemo z izgrad -njo osnovnega križa in bomo morali vprihodnosti najti čim bolj optimalnopot, kako odplačati akumulirane dol -gove, ter hkrati usteči zahtevam in pri -čakovanjem tako uporabnikov avtocestkot prebivalcev ob trasi. Ne nazadnjepa moramo imeti pred očmi, da je DARSd.d. družba s skoraj 1.250 zaposlenimiin da vodenje takega kolektiva indoseganje njegovega zadovoljstva obučinkovitem uresničevanju našega po -slan stva pomeni velik izziv že samo posebi, še posebej pa v teh časih globalnegospodarske krize, ko je še toliko težjeusklajevati želje in možnosti. Svojimsodelavcem zaupam, zato sem prepri -čana, da bomo to znali in bomo uspešniše naprej.

V velikem delu javnosti prevladujemnenje, da smo na koncu poti, sajsmo avtocestno omrežje dokončali.Ali res? Kako gledate na takšna sta -lišča?

To je sicer res na prvi pogled – osnovnoavtocestno omrežje je z nekaj manjšimiizjemami končano, vendar pa to šezdaleč ne pomeni, da smo na koncu po -ti. Ravno obratno, razlika bo samo vtem, da se bo v prihodnosti težišče na -šega dela preneslo na druga pod roč ja,predvsem bodo vse pomemb nejše nalo -ge upravljanja, vzdrževanja in obnav -ljanja. Ob naraščajočem prometu nana ših avtocestah, ki ga niti najboljopti mistične napovedi niso predvidele,namreč tako rekoč dnevno naraščapotreba po investicijskih vzdrževalnihde lih, ki bodo v prihodnosti pred stav -ljala »izziv« tako v organizacijskem kotpredvsem v finančnem smislu.

Pred nami so naloge razvoja sistemovza nadzor in vodenje prometa, kar naeni strani vpliva na večjo pretočnost inkar je še pomembnejše na večjo var -nost prometa. Zagotavljanje varnostina avtocestah mora biti ena glavnihprioritet prihodnjih let. Dejstvo je, daso avtoceste bistveno bolj varne odvseh ostalih kategorij cest, hkrati pa sožal nesreče na avtocestah zaradi višjihhitrosti mnogo bolj usodne.

Soočamo pa se tudi z vedno večjimi pri -čakovanji prebivalcev ob trasah avto -cest glede postavljanja proti hrup nezaščite in drugih ukrepov za zmanj še -vanje negativnih posledic, ki jih ob šte -vilnih pozitivnih učinkih avtocesteprinašajo okolju. Z vse večjo poselje no -stjo ob avtocestah na eni strani innaraščajočim prometom na drugi boza go tavljanje teh ukrepov v prihodnjihletih eden večjih izzivov družbe, šeposeb no, če upoštevamo omejenasred stva, ki jih bo možno namenjatitovrstnim ukrepom.

Kakšna je po vašem mnenju prio ri -teta izgradnje manjkajočih odsekov?

Dela na večini manjkajočih odsekov žepotekajo in lahko že danes s precejšnjonatančnostjo napovemo tudi njihovadokončanja – tako bo dolenjska avto -cesta mimo Trebnjega prometu preda -na še pred letošnjo turistično sezono,manjkajoči del na gorenjski avtocestipredvidoma poleti 2011, hitra cestaIzola – Koper s predorom Markovec pav letu 2013. Trenutno dela potekajotudi na Ankaranski vpadnici oziromana navezavi na Luko Koper in naodseku Gorišnica – Ormož, ravno takopa smo s pripravljalnimi deli začeli tudiglavni cesti Markovci – Gorišnica in naSrmin ski vpadnici navezave na LukoKoper.

Seveda so tukaj še odseki, ki so uvršče -ni v dodatni avtocestni program, zakatere pa predvsem zaradi nedore -čenega načina financiranja ni mogočenapovedati začetka njihove izgradnje.Ti odseki so Draženci – Gruškovje, se -ver ni del tretje razvojne osi, Postojna/Divača – Jelšane in Koper – Dragonja.Poleg tega ne smemo »pozabiti« naširitev ljubljanske obvoznice ter dogra -ditev dodatnih voznih oziroma odstav -nih pasov na določenih odsekih avto -cest.

Če se ozrem v malo bolj oddaljeno pri -hodnost in vlogo DARS d.d. kot »pra -vega koncesionarja«, pa bo moralo bitipri gradnji morebitnih novih odsekovnaše vodilo dejstvo ali je možnofinancirati njihovo izgradnjo s priliviod cestninjenja teh odsekov.

V zadnjih 10. letih beležimo naavtocestah podvojitev osebnih vozilin štiri do petkratni obseg tovornihvozil. Takšne rasti prometa ni nihčepričakoval in tudi ne napovedal.Avtoceste so te obremenitve vseenorazmeroma dobro prestale, ali ne?

Menim, da ima Slovenija dobre avto -ceste in da so le-te navkljub enor mne -mu naraščanju prometa, še posebejtovornega po vstopu Slovenije v EU,dobro prestale.

Izgradnja nekaterih odsekov našihavto cest sega v začetek sedemdesetihlet prejšnjega stoletja, zato je realnopričakovati, da so ti odseki potrebniobsežnih obnovitvenih del. Res je, dazadnja leta obnavljamo tudi odseke, kiso stari 15 ali celo kakšno leto manj,vendar pa na teh odsekih običajnoobnavljamo le zgornji ustroj ceste. Vdružbi ugotavljamo, da v Sloveniji ni -mamo dobrega nadzora nad dejan skimiosnimi obremenitvami in da so tovornavozila pogosto naložena nad dovoljenotežo.

Osebno ocenjujem, da bomo morali šebolj natančno spremljati kakovostopravljenih del s strani izvajalcev inzahtevati odpravo morebitnih napak vgarancijski dobi še bolj dosledno kot vpreteklosti. Zavedamo se, da kdor dela,dela tudi napake ampak, DARS d.d. jekot naročnik dolžan od izvajalcev do -sled no zahtevati odpravo morebit nihnapak.

Seveda pa v nedogled ne gre. Zato jepotrebno v času obnov vgraditidodat no ojačitveno asfaltno plast,kakšno obnovo pa je potrebno izvestitudi prej. S tem se povečujejo stroškiin obseg obnov. Zakaj po vašemmnenju javnost tega nikakor nerazume ali noče razumeti?

Seveda lahko uporabnike razumem, daje za njih moteča vsaka ovira na poti inna žalost obnovitvena dela so pogla -

vitni razlog za zastoje in s tem zamudena naših avtocestah in to je preprostodejstvo skozi katerega ocenjujejo našouspešnost. Z našo uspešnostjo ne mis -lim samo DARS d.d., ampak tudi inže -nirja, izvajalce, projektante, skratkacelotno gradbeno stroko. Ravno takoje pričakovano, da uporabniki težkorazu mejo, da je potrebno opraviti hra -pav ljenje betonov v komaj nekaj letstarih predorih in da tu ne pomagajopojas nila, da je npr.: hrapavljenje be -to nov v sosednji Avstriji sestavni delrednega vzdrževanja in ne nacionalnaafera, kot je bil to primer v Sloveniji.Tudi me njava dilatacij na skoraj novihviaduk tih ni nekaj pričakovanega inzato za uporabnike samoumevnega,vendar, če upoštevamo, da je bilo vzadnjih nekaj letih na slovenskihavtocestah vgra jenih več sto dilatacij,tudi to ne priča o neznanju alimalomarnosti. Je pa dej stvo, da sebomo morali v takih pri merih hitrejeodzivati in organizirati odpra vo tehnapak in prevzeti svoj del odgovor -nosti in tudi tu mislim tako na DARSd.d. kot na inženirja in izvajalce, patudi vse tiste institucije, ki so v fazigradnje izvajale kontrolo. Če se spom -nite, sta se tako menjava nekaterihdila tacij kot hrapavljenje predorovzavlekli krepko čez pol leta.

Splošno nezadovoljstvo seveda pove -čujejo tudi podatki, ki jih lahko zasle -dimo v medijih, da so dejanski stroškiobnov bistveno večji od tistih, ki jih jev letu 2004 predvidela Resolucija Na -cio nalnega programa za izgradnjoavtocest v RS. Pojasnila, da v času na -stan ka tega dokumenta ni bilo možnopredvideti takega naraščanja predvsemtovornega prometa za katere našeavtoceste niso bile ne projektirane nezgrajene, pa tudi, da so bili nekateristroški ocenjeni nerealno ipd., ne do -se žejo svojega namena.

Osebno menim, da je prav, da uporab -nikom pojasnimo, zakaj so potrebnaobnovitvena dela, da bomo povsodtam, kjer gre za napake izvajalcev le-teodpravili na njihove stroške, vendarbomo za razumevanje z njihove straninaredili največ, če bomo s skupnimimoč mi dela opravili v najkrajšem mož -nem času, če je le možno s 24 urnimdelavnikom in s takimi zapo rami, kibodo omogočile kar največjo pretoč -nost.

Vinjete so povečale dostopnost šir -šemu krogu uporabnikov. Vendar sonepravične in predvsem ne prinašajopričakovanih virov. Kako kaže z uved -bo satelitskega cestninjenja?

Pri načrtovanju razvoja cestninskihsistemov se praviloma vedno izpostavitudi vprašanje, kakšna tehnologijacestninjenja bo izbrana. Načelni odgo -vor na to daje Direktiva Evropskegaparlamenta in Sveta o intero pera bil no -sti elektronskih cestninskih siste mov vSkupnosti. Uporabiti je dovoljeno sate -litsko določanje položaja, mobilnekomunikacije GSM-GRRS in mikrovalov -no tehnologijo na frekvenci 5,8 GHz terkombinacije navedenih treh tehnolo -ških rešitev.Dosedanje naše in tuje izkušnje pakažejo na to, da so temeljni pogoj zaizbiro tehnoloških rešitev cestninjenjazahteve, ki jim mora zadostiti cestnin -ski sistem. Torej, najprej je potrebnodoločiti koncept, cestninsko shemo inposlovni model cestninjenja, odločitevo najprimernejši tehnologiji pa prepu -stiti fazi realizacije prej navedenihzahtev.

Cestninski sistem v Sloveniji že preduvedbo vinjet ni bil idealen, saj smo žetakrat imeli, in imamo še danes, t.i.zaprti cestninski sistem na primorskemkraku in odprti na vseh ostalih krakih,ter da smo s takim sistemom ocestninilimed 65 in 70% vseh po avtocestah pre -voženih kilometrov. Razmere so sedodatno spremenile še z uvedbo vinjet.Zato je Vlada RS novembra 2009sprejela Akcijski načrt za prehod naelektronski cestninski sistem v prostemprometnem toku. Ta akcijski načrtpred videva začetek cestninjenja tovor -nih vozil po prevoženih kilo metrih vprostem prometnem toku s 1.1.2012,najpozneje v letu 2014 pa tudi tovrstnocestninjenje osebnih vozil.

Glavni koraki realizacije navedenegaakcijskega načrta pred samo uvedboelektronskega cestninjenja v prostemprometnem toku so opredelitev kon -cepta ter izdelava investicijske in raz -pisne dokumentacije za vzposta vitevtega sistema. Poleg tega pa se že danes zavedamo, dabo poseben izziv uvedba cestninjenja vprostem prometnem toku glede nadejansko prevoženo število kilometrovza osebna vozila oz. vozila do 3,5 tskup ne dovoljene mase, saj takega





načina cestninjenja teh vozil ne upo -rab lja nobena druga evropska država,še posebej če k temu prištejemo šeizred no veliko količino tranzitnega pro -meta na našem avtocestnem omrežju.

DARS je na poti preoblikovanja v pra -vega koncesionarja. Nam lahko za -upa te kako poteka preoblikovanje?

Seveda je preoblikovanje DARS d.d. vpravega koncesionarja naš cilj, ki pa niodvisen zgolj in samo od nas, ampaktudi ali predvsem od našega lastnika, kiga zastopa preko resornega mini -strstva Vlada RS. Menimo, da je prvikorak v pravo smer narejen z izbiromodela lastništva in računovodskegaevidentiranja javne cestne infra struk -ture.

Računsko sodišče Republike Slovenijeje namreč na podlagi izvedene revizijesmotrnosti izvajanja in financiranjagradnje avtocest v Republiki Sloveniji vobdobju 2004 do 2007 med drugimzah tevalo, da se zagotovi izločitev pre -mo ženja Republike Slovenije v uprav -ljanju DARS d.d. iz poslovnih knjigDARS d.d. ter izvede prenos tega pre -moženja v premoženjsko bilanco drža -ve. Na podlagi tega je bila imenovanaMedresorska delovna skupina, katereglavna naloga je bila priprava analizeprednosti in slabosti različnih modelovlastništva in računovodskega eviden -tiranja javne cestne infrastrukture ternjihovih učinkov na javne finance.

Izmed treh predlaganih modelov jeVlada RS na seji 1. aprila letos odločila,da predstavlja najustreznejši modellastništva in računovodskega eviden -tiranja javne cestne infrastrukture t.i.model C. Po tem modelu postane DARSd.d. imetnik stavbne pravice na omrež -ju AC in HC, medtem ko zemljišča osta -nejo v lasti RS. DARS d.d. s tem pridobinavedeno infrastrukturo, s tem pa tudipravico pobiranja cestnine in obvez -nost upravljanja te infrastrukture terobveznost servisiranja dolgov. Zaradidržavnega poroštva, dolg DARS d.d. ševedno ostaja potencialni javni dolg,zato je usmeritev Vlade RS, da jepotreb no preučiti tudi možnost pri -vatizacije družbe.

Z morebitno uspešno (delno) priva -tizacijo družbe, bi DARS d.d. po vzorunekaterih drugih avtocestnih družb v

Evropi lahko lažje servisiral dolgovetudi iz ustvarjenega prihodka iz naslo -va novih, dodatnih dejavnosti.

Asfalterska industrija v Sloveniji jedobro razvita. V veliki meri se sleditehnološkemu razvoju najrazvitejših.Žal se včasih zalomi pri uporabi novihtehnologij na cesti. Kje je iskati vzrokza takšno situacijo? Je to morda zara -di neizprosne javnosti, ki ne dopuščanapak ali je vzrok iskati drugje?

Težko bi govorili o tem, da se pri upora -bi novih tehnologij na cestah pri naszalomi, vse doslej uvedene inovacije,naj jih naštejemo predvsem nekajnajpomembnejših – uvedba vezne pla -sti plasti med nosilno in obrabno za -por no plastjo na AC, uvedba s polimerimodificiranih bitumnov najprej vobrab nih in kasneje še v veznih plastehasfaltnih vozišč, uvedba nove vrsteasfaltne obrabno-zaporne plasti SMAali v slovenščini drobirja z bitumenskimmastiksom za najbolj obremenjenetranzitne in tudi mestne ceste – so seizkazale v največji možni meri in brezuporabe vseh teh novosti bi bilo stanjenaših cest še bistveno slabše kottrenutno je. Javnost je o tem premalo in preslaboobveščena, večinoma so to le temestrokovnih srečanj in prepričevanja žeprepričanih. Je pa zaznati trend upa -danja pripravljenosti stroke za uva -janje inovacij in novih tehnologij, takona strani investitorjev kot izva jalcev,morda ravno zaradi neizprosne jav -nosti, kajti inženirji vemo, da je žezaradi statistične verjetnosti ob če -dalje večjem številu poskusov priča -kovati tudi probleme in napake. To se jepokazalo tudi na cestah v precej boljrazvitih državah od naše in tudi tamjavnost ni bila nič kaj prizanesljiva doteh pojavov, ki pa so skoraj neizbežni –poglejte tudi veliko bolj tehnološkorazvite veje industrije, npr. avto mo -bilsko industrijo kjer se dogajajo vpo -klici novih vozil na odpravo napak, celopri največjem projektu znanosti - trkal -niku elektronskih delcev je prišlo dovelikega zastoja zaradi napak.

Vzpostavili ste dobro sodelovanje zdrugim največjim cestnim naročni -kom DRSC-jem. Ali bi kazalo boljokrepiti tudi sodelovanje na tehnič -nem področju?

Sodelovanje med obema upravljavcemaje dobro, vedno pa ga je možno tudiizboljšati ozirom razširiti. Med vidnejšerezultate tega sodelovanja v preteklemletu lahko štejemo sodelovanje naprojektu nadzornega centra v Dragom -lju, ki ga je sicer zgradil DARS d.d., vnjem pa je svoj prostor dobil tudinadzorni center DRSC. Že od leta 2006deluje tudi Prometno-informacijskicenter za državne ceste, ki skrbi zainformiranost voznikov o stanju nacestah obeh upravljavcev in ravnozaradi boljše informiranosti smo laniskupaj v sodelovanju z Ministrstvom zapromet in RTV Slovenija ustanovili tudit.i. prometni radio. V zadnjem času jebilo s skupnimi močmi veliko nareje -nega tudi na prometno-preventivnihakcijah.

Še bolj pa se bomo morali v bodočeusklajevati pri načrtovanju obnovit ve -nih del, da se ne bi dogajalo, da naavto cesti in na vzporedni državni cestihkrati potekajo obnovitve, ki bi šedodatno zmanjševale pretočnost pro -meta. Uspešno sodelujemo tudi prirekonstruiranju tistih državnih cest, kiso bile v času gradnje avtocest poško -dovane zaradi povečanega prometa to -vor nih vozil za potrebe gradbišč. Skup -na točka, kjer bomo ravno tako morališe okrepiti sodelovanje je vzdrževanjetistih objektov, kjer smo skupni uprav -ljavci npr. avtocestni nadvozi in pod -vozi.

Kje vidite največje potenciale prihod -njega razvoja avtocestnega omrežja?

Največje možnosti za razvoj vidimo vvečji uporabi recikliranih materialov vcestogradnji, s čimer bi bistveno manjobremenjevali naše okolje tako primanjših potrebah po novih gradbenihmaterialih kot pri zmanjšanem obre -me njevanju okolja zaradi manj trans -portov ter hkrati prihranili določenasredstva zaradi posledično nižjih cen. Enako pomembno je spodbujanje ino -vativ nosti, novih tehnologij in idej,kaj ti brez prenosa dosežkov raziskav izznanstvene sfere v prakso se bo raz -korak med nami in razvitimi drža vamina tem področju spet povečal, trenutnopa smo praktično na enakem nivoju inizhodiščih kot sosednje države srednjeEvrope, kar nam strokovnjaki iz tehdežel tudi priznavajo.

Najlepša hvala za pogovor! S.H.

It has been 15 years since thebeginning of an intensive period ofmotorway construction in Slovenia,during which an impressive 450 kmof motorways have been completed.Alongside numerous structures,inclu ding viaducts and tunnels, afurther 1000 km of two- and three-lane roads have been successfullyexecuted. The latter are predomi -nantly asphalt structures combinedwith cement stabilisation. Duringthe period of intensive building,according to ZAS over 5 milliontonnes of asphalt mixtures were castin motorways, which equals theamount of asphalt that Sloveniaproduces over several years. Are thepavements in Slovenia of adequatequality and durability? What are theprospects of motorway constructionand of DARS? These are just some ofthe issues we talked about with theChairman of the Board at DARS,Mateja Duhovnik.

Ms Duhovnik, you have been leadingthe Company for half a year now, aperiod which enables you to assessthe road travelled thus far. What isyour perspective on these first 6months at the helm?

My initial period as Chairman of theBoard of DARS was made a lot easier bythe fact that I had already been rela -tively well acquainted with the com -pany as I served as member of itsSupervising Committee during the1994 – 1998 and 2001 – 2003 periods.Furthermore, I was a member of theSupervising Committee for a half-year

20 from assembly to Assembly

INTERVIEW WITH MATEJA DUHOVNIK, CHAIRMAN OF THE BOARD AT DARS, MOTORWAY COMPANY OF THE REPUBLIC OF SLOVENIA

Interview withMateja Duhovnik Chairman of the Board at DARS, Motorway Company of the Republic of Slovenia

21from assembly to Assembly

INTERVIEW WITH MATEJA DUHOVNIK, CHAIRMAN OF THE BOARD AT DARS

period before being appointed Chair -man of the Board. It is true howeverthat it is only through this post that Ihave become familiar with the fullscope of activities of the Companyincluding a range of everyday issuesand challenges. I can hardly adequa -tely assess my own work during thefirst six months. I am, however, proudof the progress I and my colleagueshave made during this time. In the firstmonths since my taking over we havebeen able to escape the vicious circle ofcomplications regarding subcon tract -ing in the Markovec tunnel and werefinally able to sign the contract withthe chosen contractor before the endof last year. We also managed toacquire the two missing lots to buildthe last two sections of the motorwaypast Trebnje and finish the work on thetwo tubes of the Šentvid tunnel beforeschedule. With my coming into theCompany some key posts that had beenunoccupied were filled, which is a goodstepping-stone for our future work. Ofcourse the current financial crisis hasalso had an influence on my work whenfacing the contractors’ demands forearly payment or pressure form sub -contractors not paid by their contractpartners despite all obligations havingbeen fulfilled by DARS as the client. Iam also proud of my co-workers whomanaged in a breathtakingly shorttime to open for traffic the Trojanetunnel only a few days after a fire. Asof this year we have introduceddifferen tiated toll collection forfreight vehic les according to EUROemission clas ses, which was anespecially hard task for the companyconsidering that the existing tollingsystem had not been designed for suchtoll collection. I am aware that thecompany is now at a crucial stagewhen we have to trans form it into atrue concessionaire, whi le finishingthe construction of the basicmotorway routes. We shall have to findan optimal method of paying off theaccumulated debt, while at the sametime catering to the demands andexpectations of both the motorwayusers and the local population alongthe routes. And last but not least, wehave to bear in mind that being incharge of such a large collective asDARS, which has close to 1250 em -ploye es, and keeping the employeessatisfied while efficiently carrying outobjectives is a huge challenge in itself,

not to mention at the time of globaleconomic crisis which is making thegap between the desirable and thepossible even harder to reconcile. I,however, have trust in my colleaguesand am convinced that we will be ableto cope and continue to be successful.

A large portion of the public seems tobelieve that we are at the end of ourjourney now that motorway construc -tion has finished. Is this really thecase? What is your view of suchopinions?

At a glance, this is true. With a fewexceptions, the network is completed,but this does not mean that we havefinished – not by a long shot. On thecontrary, we are just going to shift ourfocus onto other areas, most impor -tantly management, mainte nance,and renovation. With the ever morepromi nent growth of traffic on ourroads, which even the most optimisticof predictions failed to predict, theneed for major maintenance has beengrowing daily and is set to become areal challenge in the future, bothorga nisationally and especially finan -cially.

We are facing the tasks of developingtraffic control and management sys -tems, which will increase the fluidityand, more importantly, safety of traf -fic. Ensuring traffic safety on motor -ways has to become one of our toppriorities in the years ahead of us. It isa fact that motorways are safer thanany other road category, but on theother hand traffic accidents on motor -ways are more often fatal due to higherspeeds involved.

We are also facing increasingly bigexpectations of the population inhabi -ting the areas along the motorwayroutes regarding installation of noisebarriers and other measures for pre -ven tion of undesirable consequen cesthat motorways bring to the environ -ment, despite their many favourableeffects. With the areas along the mo -tor ways being increasingly popula tedon the one hand and with the growingtraffic on the other, implementation ofthese measures will become one of thebiggest challenges of the Companyover the next years, considering thelimited funding that will be available.

How do you see the priorities regar -ding construction of the yet to becompleted motorway sections?

Work is already underway on most ofthe missing sections and their comple -tion can be predicted with fair accu -racy. The Dolenjska route past Trebnjewill open for traffic before this year’stourist season, the missing part of theGorenjska route is expected to open inthe summer of 2011, and the Izola –Koper Expressway including the Marko -vec tunnel in 2013. Currently work isunderway on the Ankaran radial roadin the Port of Koper direction and onthe Gorišnica – Ormož section, whilepreparatory work has also begun onthe Markovci – Gorišnica main road andon the Srmin radial road of the Port ofKoper junction.

Of course there are some sections thatfall into the additional programme, forwhich however the date of completioncannot be predicted mostly due to theundetermined financing method. The -se are the Draženci – Gruškovje sec -tion, the North part of the third axis ofdevelopment, and the Postojna/Diva ča –Jelšane and Koper – Dragonja sections.We must also not forget the expansionof the Ljubljana bypass and theconstruction of additional lanes andemergency lanes on certain motorwaysections.

If I venture a look into a more distantfuture with DARS being a true con -cessionaire, we shall have to be guidedin the construction of any new motor -way sections by the answer to thequestion if the construction of thesesections can be financed with incomefrom toll collected on them.

Over the past 10 years we haveexperienced a doubling of the num -ber of passenger vehicles and a four-fold rise in freight transport. Suchgrowth of traffic was unexpec ted asit was unpredictable. Despite that,Slovenian motorways have copedwith the situation well, don't youthink?

I think that Slovenia has good motor -ways that have, despite the enormousgrowth of traffic, especially freighttraffic after Slovenia’s joining the EU,coped with the situation well.

Some sections of the motorway net -work date back to the early 1970’s,which is why the need for extensiverenovation work on those sections isnot unexpected. While it is true that wehave lately been renovating sectionsonly 15 years old (sometimes evenless), this is only true of their pave -ments. We at the Company find thatcontrol over actual axial loads inSlovenia leaves a lot to be desired andthat freight vehicles are often over -loaded.

I personally believe that quality cont -rol of contractors’ work should beexecuted more precisely and that weshould be demanding elimination ofany defects that are within thewarranty period even more strictly andconsistently than in the past. Werealise that to err is human, but DARSas a client is obligated to strictlydemand of the contractor eliminationof any defects.

Of course one cannot go on like thatindefinitely. That is why anadditional strengthening asphaltlayer has been installed duringrenovations, while some renovationwork needs to be done earlier thanexpected, which raises its cost. Whyis it you think the public can’t orwon’t understand that?

Of course I can empathise with theusers and I understand that anyobstacle on their way is bothersome.Renovation is the main factor contri -buting to congestions on our motor -ways and this is the perspective fromwhich the users assess the work ofCompany, the Engineer, the contrac -tors, designers, i.e. everybody in theindustry. It is also expected that theusers find it hard to understand thatconcrete needs to be roughened intunnels only a few years old an thatexplanations to the effect that roughe -ning in Austria, for example, constitu -tes a part of regular mainte nance anddoes not warrant a public outcry suchas we have seen in Slovenia do notsuffice. Replacement of expansionjoints in recently built viaducts is notunusual or a con sequence of negligen -ce or incompe tence either, consideringthat over 100 of them were installed inSlovenian motorways over the past fewyears. It is a fact however that we shall

have to react sooner in such cases andorganise repair of such defects andbear our share of the responsibility,which goes for both DARS and theEngineer and contractors, as well as allother institutions that were in chargeof surveillance during the construc -tion. You will recall that replacement ofexpansion joints and roughening ofthe tunnels went on for a lot more thanhalf a year.

Adding to the general discontent is theinformation found in the media thatthe actual cost of renovation is a lothigher than predicted in 2004 in theresolution on the national programmeof motorway construction. Explana -tions in the vein that at the time whenthe document was being drafted suchextreme rise in (above all freight)traffic, for which our motorways hadnot been designed or built, could notbe foreseen and that some estimateswere unrealistic do not seem to reachtheir purpose.

I personally believe that we should tryto explain to the users why renovationis needed and reassure them that thosedefects that were caused by thecontractor are going to be repaired atthe latter’s expense. Yet in order for usto persuade the users, we will beperhaps best advised to do the work inthe shortest time possible, working 24hours a day and with such road closuresthat will allow adequate fluidity.

Vignettes have made motorwaysmore accessible to the general user.On the other hand, they are unjustand not generating the expectedrevenue. What is the prospect ofintroducing a satellite-based tollingsystem?

When planning development of roadtoll systems, the question is usuallyraised as to what tolling technology tochoose. A principle answer to this isgiven in the European Parliament andCouncil directive on the interope -rability of electronic road toll systemsin the Community. Satellite position -ing can be used, as can GSM-GRRSmobile communications and 5.8 GHzmicrowave technology, or a combina -tion of the three.Domestic and international experiencethus far has shown that the basic

condition in choosing the technicalsolu tion for road tolling are the requi -rements the system is expected tomeet. Only after the concept, thetolling programme, and the businesspolicy have been determined, thedecision on the best technology shouldbe made.

Slovenia’s road toll system was lessthan perfect before the introduction ofvignettes. Thus we used to have, andstill do, a so called closed toll systemon the Primorska motorway route andan open toll system on all other routes,with which we were able to tollbetween 65 and 70 % of all traffic onthe motorways. The situation changeda lot with the introduction of vignettes.This is why the Government of theRepublic of Slovenia adopted in 2009an action plan on the transition to anelectronic road toll system in freetraffic flow. The action plan providesfor tolling of freight vehicles accordingto distance travelled in free traffic flowas of 1 January 2012 and the same forpassenger motor vehicles as of 2014 atthe latest.

The main steps towards the realisationof the aforementioned action plan tobe taken before the introduction of theelectronic road toll system in freetraffic flow are the defining of the con -cept and preparation of tender andinvestment documentation for thesetup of the system.

We are aware that introduction of a tollsystem in free traffic flow based on theactual distance travelled for passengervehicles and vehicles of up to 3.5tonnes maximum permitted weight willbe quite a challenge as no other Euro -pean country currently uses a similarsystem, while also considering the factthat the amount of transit traffic onour motorway network is extremelylarge.

DARS is slowly morphing into a trueconcessionaire. Can you tell us moreabout this transformation?

Being a concessionaire is of course ourgoal, which however does not dependsolely on us, but chiefly on our owner,represented by the Governmentthrough its line ministry. We believethat the first step in the right direction





was made by determining the owner -ship and accounting models of publicroad infrastructure.

Namely, the Court of Auditors has uponthe audit of advisability of executionand funding of motorway constructionin Slovenia in the 2004 – 2007 periodrequested a removal of assets managedby DARS from the books of accounts ofDARS and transferral of these assets tothe balance sheet of the Republic ofSlovenia. Based on that an inter mi -niste rial working group was set upwhose main task was to perform ananalysis of advantages and drawbacksof various financing and accountingmodels for public road infrastructureand how they affect public finance.

The government decided in a sitting on1 April of this year that the bestownership and accounting model forpublic road infrastructure among thethree proposed models is the so-calledC model. According to this model,DARS is granted building rights on themotorway and expressway networkswhile the ownership of the land staysin the hands of the Republic ofSlovenia. With this arrangement DARSbecomes the owner of the aforemen -tioned infrastructure and is obligatedto manage it and take over its debtservice. Due to government sponsor -ship the DARS debt remains apotentially public debt, which is whythe Government proposes to look intopotential privatisation of the Com -pany.

With potential (partial) privatisation ofthe company, DARS could have a betterdebt service based on revenue from itsnew, additional activities, as can beseen in some other motorway compa -nies in Europe.

The asphalt pavement industry inSlovenia is well developed, followingfor the most part in the footsteps ofthe most advanced countries as far astechnical development is concerned.The industry provides new roadconstruc tion technologies, which arenot, however, always greeted withopen arms. What seems to be thecause of such attitude? Could that bethe ruthlessness of the generalpublic, which does not allow mista -kes, or something else?

I would not go as far as to say that newroad construction technologies are notwell received. All innovations that havebeen introduced thus far, the mostimportant ones being installation of abinding course between the base cour -se and the wearing and sealing courseon motorways, introduction of polymermodified bitumen first in wearing andlater in binder courses of asphaltpavements, and introduction of a newtype of wearing and sealing courses ofSMA for transit and urban roadssubjected to the heaviest traffic loads,have proven to be highly successful.Without them the state of theSlovenian roads would have beenconsiderably worse than it is.

The public has been insufficientlyinformed about these facts. The mediapick up for the most part only infor -mation on topics of expert meetingsand are constantly beating a deadhorse. A trend has been noted in theindustry, though, of a decreasedeager ness to accept and introduceinnovations and new technologies, byboth investors and contractors, per -haps due to the ruthlessness of thepublic. As engineers we know thatthere is a higher statistical chance of aslip-up the higher the number of trials.This was also the case with roads inmuch more developed countries thanSlovenia, where the public showed asimilarly relentless attitude towardssuch occurrences – which are, it has tobe said, almost inevitable. Just take alook at the technologically much moredeveloped industries, say the automo -bile industry, where products are beingrecalled; and even with the biggestscientific project to date, the LargeHadron Collider, there has been a delaycaused by human error.

You have set up a good collaborationwith the other biggest road construc -tion contracting authority, DRSC, theSlovenian Roads Agency. Are you alsolooking to strengthen your collabo ra -tion in the technical field?

Although the collaboration betweenthe two overseers has been good, weare always looking for improvementsand extensions. Among the most no -table results of our collaboration inthe past year is the establishment ofthe Dragomelj traffic management

centre, which was built by DARS butshares the premises with DRSC controlcentre. Also, the Traffic informationcentre for public roads, which hasbeen in operation since 2006, informsmoto rists on road conditions on theroads managed by both overseers. It iswith the aim to better inform moto -rists that we created the so-calledTraffic Radio last year together withRTV Slovenia. A lot has been donelately in the field of prevention oftraffic accidents as well.

We shall have to be better coordinatedin the future in planning renovationworks in order to prevent simultaneousrenovations on both motorways andtheir corresponding public roads,which would additionally impedetraffic flow. We have been successfullyworking together in reconstruction ofthose public roads that were damagedduring motorway construction due toan increase of freight vehicle traffic forthe needs of the construction sites.Another common activity where weshall have to strengthen our collabora -tion is maintenance of those structuresthat we manage jointly, i.e. motorwayoverpasses and under passes.

What are, in your opinion, the big -gest potentials of the future deve -lopment of the motorway net work?

The biggest development possibilityhas to be a more extensive use ofrecycled materials in road construc -tion, which would considerably reducethe burden on the environment be -cause of the lesser need for newconstruction materials and transport,while at the same time saving somefunds due to lower costs.

It is equally important to stimulateinnovativeness and creativity in thefield of new technologies. Withouttranslation of research into practicethe gap between us an the developedcountries in the field will once againbegin to widen, as we are now virtuallyon the same level and with the samestarting points as the neighbouringcentral European countries, a fact thatis acknowledged by these countries’experts.

Thank you very much for your time. S.H.

VOZIŠČNE KONSTRUKCIJE NA AVTOCESTAH IN V PRE -DORIH – ASFALT ALI BETON?

UvodGlavnina izgradnje nacionalnega avto -cestnega programa je z odprtjem avto -cest mimo Maribora in čez Reber nice vtednu med 10. in 15. avgustom 2009končana. Prišel je čas, da se naredijoresne ekonomske, tehnične, sociološkein druge analize uspešnosti oziromaneuspešnosti največjega dose danjegainfrastrukturnega projek ta v Sloveniji.Ali je bil res predrag in časovno prevečrazvlečen, kot se ga v zadnjem časustalno prikazuje v medijih? To namrečne bo edini tak projekt, saj nekaterinacionalni razvojni dokumenti predvi -devajo dodatne investicije na področjucest, železnic, energetike, vzpostavitvegospodarskih središč in druge. Te inve -sticije so potrebne in bodo gonilo nada -ljnjega gospodarskega razvoja države.

Komentarji, ki so v zadnjih letih sprem -ljali izgradnjo avtocestnega programaso bili vse prevečkrat slikani izrazitonegativno in konec izgradnje kaže, kotda z zgrajenimi avtocestami ni zado -voljen nihče.

V zadnjem času so se v javnosti pojav -ljale številne strokovne dileme, nakatere pa običajno ni bilo pravih in ute -meljenih odgovorov. Lahko bi celo re -kel, da je - običajno brez ustreznihargu mentov - obveljalo mnenje, kakoje vse narobe.

Tako se je jeseni 2009 v ospredju poja -vila dilema o vrsti voznih površin v na -

ših predorih, ali beton ali asfalt. Poslu -šamo vsemogoča mnenja, med katerimije zaslediti tudi povsem pomanjkljive innapačne informacije, kako asfalt niustrezen za uporabo v predorih, saj jegorljiv in manj vzdržljiv od cementnegabetona.

V prispevku bi rad prikazal nekateredile me, ki so spremljale gradnjo inkako smo se odločali za posameznerešitve pri gradnji voziščnih konstrukcijna avtocestah.

Kako se je začelo?Pričetek izgradnje avtocest s prvimiaktivnostmi v letu 1993 in prvim Nacio -nalnim programom izgradnje AC v RS vletu 1995 je bil zaznamovan z vzne -senostjo, pozitivno energijo in super -lativi. Dolžina dotedaj zgrajenih avto -cest je bila znatno premajhna, da bizagotavljala primerno mobilnost inpretočnost cestnega prometa.

Prišle so prve otvoritve AC odsekov, ACČebulovica – Divača, odprta 12. julija1995, kateri so sledili novi odseki. Obli -kovan je bil uspešen model finan -ciranja, sistem oddaje del, gradnje,nadzora in delovanja kontrole kvali -tete. Pojavil se je slogan »Slovenijagradi avtoceste«, kolesje na čelu sprvim predsednikom uprave DARS-a seje zavrtelo. Načrtovalcev, projektan -tov, tehnologov, neposrednih gradite -ljev, nadzornikov in dobaviteljev je prigradnji avtocest sodelovalo več tisoč.

Seveda so se pri tako velikem in dolgo -trajnem projektu pojavili tudi posa -mez ni ekscesi, ki pa ne morejo pokva -riti slike uspešne realizacije zastav -

ljenih ciljev in izničiti dela številnihstrokovnjakov, ki so sodelovali pri temprojektu, zato tudi ni prav, da se pre -večkrat vse meče v isti koš.

Velika večina udeležencev je predanoin uspešno opravila svoje delo. Prvi ciljstrokovnjakov, ki smo se ukvarjali zvozišči, je bil odpraviti kolesnice (slika1) z naših avtocest. In teh ni bilo malo.Ogrožale so prometno varnost inudobnost vožnje. Poglobljeno strokov -no razvojno-raziskovalno delo, pove -zo vanje strokovnjakov doma in stujino, ki so dajali ustrezne napotkeindustriji asfalta, je omogočilo kako -vost naših vozišč, kot jih imamo sedaj.V ta namen so bili med drugimi ukrepivpeljani številni postopki labora torij -skih preskusov in analiz (slika 2).

Voziščne konstrukcije na avtocestahVoziščna konstrukcija je zaključni delceste, sestavljena iz različnih plastinevezanih in vezanih materialov, pokateri se odvija promet. Vezane plastipredstavljajo tudi zaključni sloji izasfalta ali cementnega betona. Ker sepo tej plasti odvija promet, kateremu jecesta namenjena, govorimo o enem od


STROKOVNI PRISPEVKI

Strokovni prispevki

Slika 1: Kolesnice na AC Vrhnika -Logatec v letu 1993


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najpomembnejših elementov ceste. Odvoziščne konstrukcije, ki jo zaključujevozna površina, je odvisna varnost pro -meta, udobnost vožnje, hrupnost voz nepovršine in tudi življenjska doba ceste.

V nekaterih državah, ki imajo podobnodobro razvito tako (cementno) beton -sko kot asfaltno tehnologijo gradnjevozišč, sta obe tehnologiji predmetostrega konkurenčnega lobiranja, gle -de na to, da ima vsaka svoje prednosti

in pomanjkljivosti. Tudi v Sloveniji smopred pričetkom intenzivne izgradnjeavtocest v letih 1993 in 1994 bili v dile -mi, katero tehnologijo izbrati. Posebnaštudija, ki je bila izdelana v nekdanjemCestnem inženiringu (predhodnikuDDC-ja), je dajala glede mehanskihkarak teristik in trajnosti prednost be -tonu.

V tistem času je vsaj 10 domačih pod -jetij obvladovalo asfaltno tehno lo gijo,betonske pa v pravem pomenu besedenobeno. Tehnologija izvedbe betonskihvozišč je tako tehnološko kot logističnozahtevnejša kot asfaltne. Prometneobremenitve pred 15. leti so bile ne -primerljive z današnjimi. Le na redkihodsekih je bilo več kot 1000 težkihkamionov na dan in tudi prometne štu -dije za naslednjih 20 let nikakor nisopredvidevale današnjega stanja, kar jev tistem času odločilno pogojevaloodlo čitev za asfaltna vozišča.

Asfaltno vozišče praviloma nudi večjoudobnost uporabniku, je manj hrupno,omogoča lažjo nadgradnjo (ojačitev)in vzdrževanje (npr. krpanje). Na drugistrani pa so prednosti betonskega vo -zišča predvsem v svetlosti vozne povr -šine, v stabilnosti (se ne defor mira) inposledično v večji trajnosti. Slednja jetudi posledica debelin, ki mora biti pribetonskem vozišču vsaj 24 ali 25 cm.Asfaltne voziščne konstrukcije somanj ših debelin, na avtocestah pri nasso vgrajene v debelinah med 17 in 23cm, izjemoma tudi manj. Zaradi nave -denega so asfaltna vozišča tudi konku -renčnejša oziroma cenejša.

V Sloveniji zaradi navedenih dejstevprave konkurence med obema tehno -logijama ni. V strokovnem smislu pa sedaje podpora betonskim voziščem, kiso pravzaprav alternativa, ko se dose -žejo ekstremne obremenitve.

Torne lastnosti so pri obeh vrstahvozišča odvisne od vrste uporabljenegamateriala. V zadnjem času se tako priasfaltnih kot betonskih voziščih vpretežni meri, to je za zrna velikostinad 2 mm, uporabljajo samo silikatne(eruptivne) kamenine, ki zaradi visokeodpornosti proti poliranju (zagla -jevanju) zagotavljajo trajnejšo odpor -nost proti drsenju. V preteklosti se jepri obeh vrstah voznih površin uporab -ljalo kamene materiale, sestavljene izpribližno 50 % silikatnih zrn in 50 %karbonatnih zrn, ki sicer ne nudijo takodobrega odpora proti drsenju, zago -tavljajo pa večjo trajnost zmesi oziro -ma mešanic. Glavni razlog te uporabeje dejstvo, da je bila na eni stranikvaliteta voznih površin primerna, nadru gi pa je bilo možno uporabiticenejše domače kamnite materiale -apnence, saj se pretežni del eruptivcevuvozi iz Avstrije ali Hrvaške.

DARS je na avtocestah po letu 2000vpeljal sistem permanentnih meritevstanja voznih površin v povezavi zgospodarjenjem z voznimi površinamiPMS (Pavement Management System),na osnovi katerega se določajo ukrepiza obnove oziroma sanacije. Na osnovitega švicarsko-kanadskega sistema, kiga je v Slovenijo vpeljal in za našepogoje razvil DDC svetovanje inže -niring, je bilo pri meritvah v letu 2005ugotovljeno, da je kakovost torne spo -sobnosti voznih površin v predorihslabša kot na odprtih trasah. Po teh

Slika 2: Preskusa odpornosti asfaltne plasti pri nizkih in visokih tempe raturah

VAC Ljubljana

Slika 3: Tipična poltoga voziščna konstrukcija na avtocesti

merilih je bila ogrožena varnost pro -meta. Na osnovi ugotovitev je bilapred lagana takojšnja sanacija zgla -jenih vozišč. Problematika je bila zelotendenciozno predstavljena v javnostiin je povzročila znano afero o drsnostivozišč v trojanskih in drugih predorih.

V teh predorih je izredno hitra rast šeposebej težkega prometa v povezavi sposebnimi pogoji, ki delujejo v pre -dorih, povzročila nepričakovano hitrozaglajevanje vozne površine. Ta je bilaob izgradnji obdelana z juto, ki niomogočila, da bi okoli 50 % zrn sili -katnih kamnin stopilo na površje.Sana cija z rezkanjem, opravljena v letu2008, je omogočila odstranitev ce -men tnega mleka na površini in zago -tovila prisotnost eruptivnih zrn, kinudijo primerno mikro in makro hra -pavost, s čimer je sedaj v vseh ohra -pavljenih predorih zagotovljena pri -mer na torna sposobnost voznih povr -šin. Opravljajo se redne meritve. Vprvem letu po opravljenih rezkanjih niznatnega poslabšanja tornih lastnosti,kar samo dokazuje, da je bil problemizgradnje betonskih krovnih plastipredvsem v neustrezni obdelavi povr -šine z juto. V poznejših gradnjah je bildodatno povečan delež eruptivnihzme si zrn s 50 na npr. 75 m/%, kar šedodatno izboljšuje torne lastnostivozišč.

Izgradnja betonskih vozišč v trojanskihpredorih je bila skladna z znanjem, ki jebilo tedaj prisotno in ki je bilo zelopodobno znanju v evropskih državah,kjer gradijo betonske ceste (Nemčija,Avstrija, Švica, Belgija) in jih po potre -bi tudi hrapavijo. Sedanja izvedbabeton skih vozišč odpravlja ugotovljenepomanjkljivosti, zato ni razlogov, da sene bi gradilo cest s cementno beton -skimi krovnimi plastmi.

Prometne obremenitve na avtocestahPromet na cestah se prikazuje s pov -prečnim letnim dnevnim prometom(PLDP) vseh vozil in s prometno obre -menitvijo (PO), za kar vpliv vozil gledena težo in število osi pretvorimo naštevilo prehodov nominalne osne obre -menitve 82 kN (8,20 tone) ali v zad -njem času na 100 kN (10 ton). Na pro - metno obremenitev vplivajo pred vsemtovorna vozila. Količina prometa(PLDP) vpliva na pretočnost ceste, veli -ke prometne obremenitve pa pov zro -čajo predvsem utrujanje = poškodbe na

infrastrukturi. Za vsak odsek pose bej sev fazi načrtovanja izdela poseb na pro -metna študija, ki običajno za 20 letnapove obseg, strukturo in narašča njeprometa. Študije, ki so bile izdela ne vzadnjih 15. letih, so zelo dobro napo -vedovale PLDP. Velika odstopanja pa sose zgodila pri napovedih PO. Če so bilevse napovedi rasti PO med 3 in 4 %letno, lahko za zadnjih 10 let na posa -meznih avtocestnih krakih ugotovimo4 do 5 krat večje povprečne rasti (med16 in 17 % letno (graf 1)). Gre zaekstrem no velika odstopanja, ki soposledica številnih faktorjev, kot npr.vstop številnih držav v EU, izjemnagospodarska rast Slovenije v zadnjihletih, dokončanje posameznih krakovavtocest in drugo.

Slovenija je z rastjo prometnih obre -menitev, ki so predvsem posledica enor -mnega povečanja težkih tovor njakov invlačilcev (s 1000 na do 5000 vozil dnev -no), preskočila nekaj razre dov in sepribližala prometnim obre menitvamnajrazvitejših evropskih držav. Nave -deno ima seveda izjemen vpliv na ceste,predvsem na voziščne konstrukcije, kiso bile dimenzionirane na veliko manjšepričakovane promet ne obremenitve.Zato nas seveda ne sme jo čuditi številniposegi in obnove na obstoječihavtocestah, kjer se poleg preplastitevpraviloma izvajajo tudi potreb neojačitve. Ukrepi so določeni s prejomenjenim sistemom PMS, ki temelji naprincipu optimiranja stro škov in koristiuporabnikov in uprav ljalca.


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Graf 1: Povprečna letna stopnja rasti po vrstah vozil in po krakih za obdobje1998 -2008

Graf 2: Povprečno letno dnevno število priklopnikov za obdobje 1998 -2009 pokrakih


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Asfalt ali beton v predorihNe glede na to, da so se na avtocestahpretežno gradile asfaltne ceste, je bilana začetku izvedbe avtocestnega pro -grama sprejeta odločitev, da se vposebnih pogojih prične z gradnjobetonskih vozišč. Najprej so bili topredori Golo Rebro in Pletovarje naŠtajerskem in predor Tabor na Pri -morskem, ki jih je izvajal SCT z najetimnemškim betonskim finišerjem. Vnadaljevanju, ko je bila v letu 1999sprejeta usmeritev, da se betonskavozišča poleg predorov izvaja tudi nacestninskih postajah in na pasovih započasni promet, pa se je SCT opremil zustreznim finišerjem in samostojnopričel z izvajanjem teh del. Ostali izva -jalci se niso odločili za nabavo teopreme, saj so očitno ocenili, da je tehdel premalo. Dejansko se je v zadnjih10 letih zgradilo predore preko Trojan,predora Dekani in Kastelec, okoli 10 kmpasov za počasni promet in nekaj cest -ninskih postaj, vse skupaj okoli 30 km(ali 2 %) pri skoraj 1.500 km smernihvozišč na avtocestah. Razvoj pri takomajhnemu obsegu del je seveda ote -žen, vseeno pa za razliko od številnihevropskih držav (npr. Italija, Francija,Hrvaška) v Slo veniji betonske cestegradimo in jih tudi razvijamo.

Razlog za odločitev, da se v predorihgradi betonska vozišča, je bila pred -vsem v njegovi svetli površini. Ostalirazlogi, ki se jih pogosto navaja vjavnosti, kot so bistveno večja trajnostin negorljivost, niso točni, večkrat socelo zavajajoči.

Asfalt je zmes kamenega materiala,kamne moke in bitumna. Bitumen kotnaftni proizvod je sicer gorljiv, vendarv asfaltu skupaj s kameno moko tvoribitumensko malto, ki preprečuje go -renje in so zato argumenti o gorljivostibrezpredmetni. Zaradi več požarov vpredorih v območju Alp v obdobju 1999in 2005 je bilo na to temo opravljenihveč študij in analiz. Opravili so tudiprimerjavo med uporabo asfalta ozi -roma betona v predorih. Posebnoštudijo je izvedel tudi tehnični odborPIARC C5 »Road Tunnels Committee«.Zaključki komiteja svetovnega cest -nega združenja so naslednji: »Iz vsehdokumentiranih izvedenih študij inraziskav je evidentno, da asfalt kotmaterial za vozišča nima bistvenegavpliva na velikost in jakost požara vprimeru, da do njega v predoru pride.

Asfaltno vozišče nima bistvenega vplivana varnost v primeru požara in se lahkouporablja v cestnih predorih.« Prav takovladajo v predoru stabilni vremenskipo goji (ni velikih tempe ra tur nih raz -lik), ki ob podobno vgrajenih debe -linah asfaltu zagotavljajo dokaj pri -merljivo življenjsko dobo kot betonu.Edina bistvena slabost asfalta je torejmanjša svetlost vozne površi ne, kar paz nekoliko večjo osvetlitvijo elimini ra -mo, lahko pa se uporabljajo tudi svet liasfalti z uporabo svetlejših kamenihzmesi in sintetičnih veziv.

Torne lastnosti vozne površine soodvisne od uporabljenih kamnin, pričemer so torne lastnosti ne glede navozno površino v predoru slabše, kar jepo doslej znanih podatkih predvsemposledica drugačnih pogojev glede naodprto traso, ki je podvržena vre -menskim vplivom (Poročilo EAPAAsphalt pavements in tunnels). Vpredorih se na površini nabira prah,saje in ostanki pnevmatik, zato jepotrebno tako betonsko kot asfaltnopovršino redno prati in čistiti.

V Evropskih državah je z asfaltnimvoziščem zgrajenih več sto kilometrovpredorov. Najdaljši med njimi soLaerdalstunnel (l = 24,510 m) naNorveškem, Toulon (l = 3,200 m) vFranciji, prečkanje Elbe (3,543 m) inA71 pri Suhl-u (7,900 m) v Nemčiji,Oresund tunel (3,510 m) na Danskem,

Westerscheldetunnel (6,600 m) naNizozemskem in drugi.

ZaključekOsnovni avtocestni program je v fazizaključevanja. Avtoceste dobro oprav -ljajo svojo funkcijo, vsak dan se po njihvozijo deset tisoči uporabnikov.

Če smo v letu 1993 ugotavljali, da soštevilne naše asfaltne ceste defor -mirane v obliki kolesnic, tega danes neglede na veliko večje prometne obre -menitve ni več. Vozišča imajo primernokakovost, ki zagotavlja ustrezno var -nost prometa in uporabnikom udob novožnjo.

Obseg gradnje betonskih cest v pre -teklosti ni omogočal vsega potreb negarazvoja, ne glede na to pa to tehno -logijo v Sloveniji obvladujemo in joznamo uporabljati. Ekstremne promet -ne obremenitve v zadnjih 10-ih letihnarekujejo potrebo po dodatnih ojačit -vah asfaltnih vozišč v prihodnje, šeposebej če se bo trend rasti nadaljeval.

V cestnih predorih se lahko enako -vredno gradijo tako asfaltna kot beton -ska vozišča, pri čemer je v obeh prime -rih potrebno zagotavljati ustreznočiščenje (pranje z visokim pritiskom)voznih površin za zagotavljanje ustrez -nih tornih lastnosti in prometne var -nosti.

Slovenko Henigman, univ. dipl. inž. grad.Direktor za področje avtocest DDC svetovanje inženiring d.o.o.

Viri: • EAPA »Asphalt pavements in tun -

nels«, maj 2008• Interna gradiva DDC svetovanje

inženiring, d.o.o.

Slika 4: Beton v predoru Golovec in napasu za počasni promet na AC Klanec-Srmin, 2004

Slika 5: Asfalt v predoru Leščevje nadolenjski avtocesti, 2008

GUMIRANE ASFALTNE ZMESI

UvodV svetu se vsako leto pojavlja namilione odpadnih avtomobilskih gumpa tudi gum tovornih vozil. Samo vSloveniji, po podatkih statističnegaurada, v zadnjih letih zberemo do18.000 t odpadnih gum letno. Več kotpolovica zbranih gum se kot gorivosežge v pečeh v cementni industriji, karv veliki meri doprinese h količinamizpustov CO2 v Sloveniji. Manj kot polo -vica zbranih starih gum se tako ali dru -gače predela. Predelovalca, ki bi lahkopripravil gumene delce za uporabo vasfaltnih zmeseh, trenutno v Slovenijinisem zasledila.

Obstaja več metod, kako gume koristnopredelati in ena izmed metod je drob -ljenje gum v delce, ki jih uporabimo zamodifikacijo bitumna. Raziskave natem področju so obetajoče, kar pomenikoristno rešitev za velike količine zbra -nih odpadnih gum pa tudi za razvojtrajnejših asfaltnih plasti.

Dodajanje gumenih delcev v bitumenizbolj ša lastnosti bitumna, ki so pove -za ne z obnašanjem (performance-rela -ted). Asfaltne zmesi, ki jih proizvajamoz gumibitumnom so bolj stabilne inbolj elastične ter tako bolj odpornepro ti preoblikovanju kot podobnezmesi s klasičnim bitumnom.

Izkazujejo večjo odpornost na eks -trem ne temperature - torej visoke, karizboljša odpornost proti tvorbi kolesnicin nizke temperature, kar izboljša od -por nost proti pojavu razpok. Poleg te -ga so bolj odporne proti spremem bam,ki jih sicer pogojuje staranje bitu men -skega veziva. To pomeni, da se po ve čaodpornost proti utrujanju asfaltneplasti in s tem poveča trajnost asfaltneplasti.

Zaradi elastičnih lastnosti gumiraneasfalt ne plasti se zmanjša obrabapnev matik vozil.

Z ustrezno izbiro vrste gumirane asfalt -ne zmesi lahko precej zmanjšamo nivohrupa, ki ga doprinaša asfaltna površi na.

Preplastitve z gumirano asfaltno plast -jo zmanjšujejo poškodbe, ki reflekti -rajo iz spodnjih plasti asfalta.

Površina gumiranega asfalta dalj časaohrani črno barvo, kar omogoča večjotransparentnost barvnih oznak.

Strokovnjaki, ki se intenzivno ukvarjajoz gumiranimi asfaltnimi zmesmi inplastmi dokazujejo, da je proizvodnjagumiranih asfaltnih zmesi sicer dražjaod klasičnih vrst, je pa lahko debelinavgra jevanja plasti manjša in vzdrže -vanje teh plasti bitveno cenejše.

MaterialiBitumenKemijska sestava bitumna je zelo raz -no lika, saj ga sestavlja veliko različnihorganskih spojin, katerih natančnaidentifikacija zaradi velike podobnostimed njimi pogosto ni možna. Sestavaje odvisna od izvora nafte ter rafina -cijskega procesa. Kemijska sestava bi -tum na in temperatura imata močanvpliv na mehanske lastnosti ter namikrostrukturo bitumna. Kot vhodnibitumen se izbere cestogradbeni bitu -men, ki sicer ustreza klimatskim razme -ram in namenu uporabe.

Gumeni delciGumena zmes iz katere je izdelanavtomobilski plašč, je kombinacija na -rav nega in sintetičnega kavčuka (naj -po gosteje uporabljen je stiren-buta -dien SBR), različnih sestavin nafte,kemikalij in saj. Za podaljšanje življenj -ske dobe in ohranjanje prvotnih last -no sti prožnosti, osnovnim sestavinamdodajajo optimirane zmesi voskov,antioksidantov in antiozonatov.

Gumeni prah oz. gumene delce iz od -pad nih gum proizvajajo z dvema po -stop koma: mletjem pri temperaturiokolice (ambientni postopek), kjer sedelci bolj cefrajo in mletjem s krioge -nim postopkom, kjer se delci gumeohlajajo s tekočim dušikom in drobijo.Pri obeh postopkih se odstranijo kovin -ski delci (žica v postopku drob ljenja zmagneti) in delci tkanin z izpiha -vanjem. Z obema tehnikama si cer pri -dobimo delce podobne velikosti, ki pase razlikujejo v površinskih lastnostih.

Za modificiranje bitumna so, zaradireakcijske površine, primerni delci, ki jihpridobimo z ambientnim postop kom.

Iz ene tone odpadnih gum dobimo od400 – 700 kg gumenega granulata in150 – 250 kg odpadnega jekla, ki ga jemožno prav tako uporabiti kot sekun -darno surovino. Ostalo so neuporabniodpadni materiali.

Delci gume se označujejo s CRM (crumb

rubber modifier), saj nji hova uporabamodificira lastnosti vro če asfaltnezmesi in plasti.

DodatkiKot dodatki pri proizvodnji z gumomodificiranega bitumna se uporabljajoapno, polifosforna kislina, amini odvis -no od namena uporabe s tem bitum -nom proizvedene asfaltne zmesi. Vsakod navedenih dodatkov spremeni dolo -čene lastnosti RmB.

Priprava z gumo modificiranega bitum -na RmB (rubber modified bitumen)Do sedaj je bilo dokaj malo uspeha priugotavljanju interakcije med gumo inbitumnom in tudi različni podatki senajdejo v literaturi o nabrekanju gumev bitumnu. Vzrok je lahko v razlikah vtopnih parametrih komponent z na -rašča jočo temperaturo.

Ko se gumeni delci potopijo v bitumen,le-ti absorbirajo komponente podobnetopnosti in hitro nabreknejo. Močnetrans vezi (cross-links) med elasto -mernimi verigami preprečujejo gume -nim delcem, da bi se v celoti raztopili vtekočem bitumnu. S podaljševanjemreakcijskega časa tekočina penetrira vnotranjo strukturo polimera in nabre -kanje narašča. Ugotovili so, da potekanabrekanje linearno prvih 90 s, nato panarašča z upadajočo hitrostjo. Gumenidelci lahko nabreknejo 3-5 krat gledena začetno prostornino. Nabrekanjegumenih delcev v bitumnu je odvisnood temperature in kontaktnega časa,


STROKOVNI PRISPEVKI

Ambientni postopek

Kriogeni postopek


STROKOVNI PRISPEVKI

kemijske sestave bitumna (vsebnostilažjih frakcij), tipa gume in velikostidelcev. Kemijska narava bitumna dolo -ča ravnotežno vrednost nabrekanja,medtem ko viskoznost bitumna določahitrost nabrekanja.

Za pripravo gumibitumna so primernidelci gume do velikosti največ 0,8 mm,torej gre bolj za gumeni prah. V cesto -gradbeni bitumen se dodajajo različnemnožine gumenih delcev, od 5 m% do20 m%, odvisno od narave vhodnegabitumna in želenih končnih lastnostigumibitumna. Guma se dodaja v vročbitumen (190 – 230 °C) in meša dolo -čen čas (do 1 ure), da nabrekne. Natose gumibitumen hrani pri temperaturi175 °C. Gumibitumen trenutno še nimadobrih skladiščnih sposobnosti, zato sega proizvaja na mestu proizvodnjeasfalt ne zmesi in se ga mora uporabitiv roku 24 ur. Sicer se zgodi, da začnejopolimeri, ki nastajajo razpadati, kar seugotovi z merjenjem viskoznosti. Če sepred uporabo lastnosti gumi bitumnaspremenijo, mu je treba dodati takosveže gumene delce kot sveži bitumen,da se ponovno dosežejo zahtevanelastnosti.

V ZDA so razvili ustrezno tehnologijo zaproizvodnjo GmB. Mešalnice se medsabo nekoliko razlikujejo po načinume ša nja in kapaciteti.

Proizvod RmB je v ZDA standardiziran,njegove lastnosti morajo ustrezatizahtevam standarda ASTM D 6114-97(2002). Navedeni standard vsebujepoleg zahtev za RmB še zahteve zavhodne materiale, to je gumene delcein vhodni cestogradbeni bitumen inpredpisuje postopke preverjanj. RmBrazvršča v tri tipe glede na uporabo vrazličnih klimatskih področjih. Klimat -ske razmere so določene z minimalnoin maksimalno povprečno mesečnotem peraturo. Tako je: • vroča klima, če so povprečne meseč -

ne temperature med -1 °C do + 43 °Cin se priporoča uporaba tršegavhod nega bitumna. Zameša se GmBtip I (PG 65-16).

• mešana klima, če so povprečnemeseč ne temperature med -9 °C do+43 °C in se priporoča uporaba ne -ko liko mehkejšega vhodnega bi tum -na. Zameša se GmB tip II (PG 58-22).

• Mrzla klima, če so povprečne meseč -ne temperature med -9 °C do + 27 °Cali nižje in se priporoča uporabamehkega vhodnega bitumna. Zame -ša se GmB tip III (PG 52-28).

Proizvodnja gumiranih asfaltnih zmesiDelce iz odpadnih gum lahko vnesemov asfaltno zmes na dva načina, ki juimenujemo mokri in suhi postopek. Posuhem postopku delci gume pred -stavljajo delež v fini frakciji kamnitegamateriala, po mokrem postopku padelci gume predstavljajo modifikatorbitumna in z gumo modificiran bitu -men se uporabi za proizvodnjo vročeasfaltne zmesi.

Suhi postopek:Suhi postopek je primeren za vročeasfaltne zmesi tipov bitumenskihbetonov AC, SMA ali drenažnih asfaltovPA, ni pa primeren za proizvodnjohladnih asfaltnih zmesi ali površinskihprevlek. Po suhem postopku se dodajagumeni granulat kot nadomestilo finefrakcije (od 1 do 3 % teže kamnitegamateriala v zmesi). Delci gume senajprej mešajo s kamnitim materialom,nato se dodaja bitumensko vezivo inpolnilo.

Suhi postopek so razvili Švedi v poznih60-ih letih in ga patentirali pod ime -nom PlusRide.

Gumeni granulat je vseboval delce od4,2 do 2,0 mm. Ciljna votlavost zmesi jebila od 2 do 4 %, kar se ponavadi dose -že z vsebnostjo bitumna od 7,5 do 9 %.

Suhi postopek se je v zgodnjih devet -desetih letih izboljšal tako, da se upo -rab ljajo tako grobi kot tudi fini delcigume, ki se predhodno prepa rirajo ssnovjo, ki izboljša nabrekanje delcev. Vzadnjem času se dodaja do 2 % gu -menih delcev glede na težo celot neasfaltne zmesi drobnejše granu lacijeza bitumenski beton AC surf.

Zrnavost kamnitih frakcij je potrebnosprojektirati tako, da je dovolj prostora

za gumene delce. Nezreagirana guma»postane« volumsko kot kamnita frak -cija in zapolni prostor. Za bitumenskebetone z manjšo nazivno zrnavostjo jepotrebno uporabiti drobnejše frakcijegumenih delcev. Gumeni delci naj bodočim bolj suhi, naj ne bi imeli več kot0,75% vlage, kar je posebej pomembnopri mokrem postopku.

Delci se lahko za proizvodnjo bitu -menskega betona dodajajo preko silosaza celulozna vlakna, lahko preko siste -ma za doziranje asfaltnega granulataali se vreče z odmerjeno množino del -cev mečejo v mešalec ročno. Dodanamnožina gumi granulata mora biti nad -zorovana in vedno enaka, saj ima velikvpliv na pričakovane lastnosti gu miraneasfaltne zmesi po suhem postop ku.

Pri mešanju je pomembno, da se po -daljša čas mešanja in poviša tempe -ratura kamnite zmesi. Najprej je pot reb -no gumeni granulat in kamniti materialsuho mešati, da se kamniti in gumenidelci dobro premešajo pred dodajanjembitumenskega veziva. Tem peraturaasfaltne zmesi naj znaša od 149 °C do177 °C. Proizvedena gu mi rana asfaltnazmes naj se v silosu kondicionira 1 uro,predno se odpelje na gradbišče.

Mokri postopek:Proizvodnja vročih asfaltnih zmesi pomokrem postopku je pravzaprav enakakot proizvodnja klasičnih asfaltnihzmesi. Potrebno je, da je asfaltni obrattehnološko prilagojen temu načinu pro -izvodnje. Opremljen mora biti z mešal -nico gumibitumna, imeti dovolj močnečrpalke za pretakanje bolj vis koz negaveziva in imeti dovolj velike šobe, kiprepuščajo nabrekle gumene delce.

Več pozornosti je tako potrebno po -svetiti vhodnim materialom za pripravoz gumo modificiranega bitumna inpostopku mešanja. Znano je namreč,da vsi viri bitumnov niso primerni zamodificiranje z gumo. Tako je potrebno preveriti:• vir in tip bitumenskega veziva, • vir in granulometrijo gumenih del cev, • raziskati potrebni dodatek gumenih

delcev k bitumnu, da se dosežejoželene lastnosti, primeren reakcijskičas,

• temperaturo mešanja, • intenziteto mešanja,• potrebo po morebitnem dodajanju

aditivov.

Vzorec z gumo modificiranega bitumna

Mokri postopek je primeren za vse vrstevročih asfaltnih zmesi, kot tudi zapovršinske prevleke, antistresne mem -bra ne, ki se vgrajujejo med plastmi alikot vrhnja plast.

Vgradnja gumiranih asfaltnih zmesiPri bitumenskih betonih je za pred -videno debelino plasti potrebna enakakoličina gumirane asfaltne zme si kotpri konvencionalnih zmeseh. Pri gumi -ranih drobirjih z bitumenskim mastik -som je treba računati z nekoliko večjokoličino materiala za isto debe lino kotpri SMA.

Pri prevozu gumirane asfaltne zmesi nagradbišče se priporoča, da se kesonitovornjakov ne pobrizgajo z nafto, am -pak z milnico ali vodno emulzijo sili -kona. Predpostavljam, da je naše repič -no olje prav tako primerno. Naftanamreč reagira z gumenimi delci, karlah ko vpliva na lastnosti gumiraneasfalt ne zmesi.

Pomembno je, da se gumirani asfalt nevgrajuje pri temperaturah, ki so nižjeod 10 °C, poleg tega pa tudi debelinaplasti, ki se vgrajuje, naj ne bi presegla3 cm, saj se potem pojavijo težave prizgoščanju plasti.

Temperatura asfaltne zmesi pred začet -kom vgrajevanja mora znašati od 120 °Cdo 160 °C. Zaključno valjanje se moranadaljevati, dokler temperatura plastine pade pod 60 °C (ponekod piše pod100 °C), da se prepreči nabrekanjekom pak tiranih gumenih delcev.

Za vgrajevanje se ne sme uporabljatipnevmatskih valjarjev, ker se guma pri -me na gumi oblogo valjarja. Svetuje seuporaba najmanj treh 8 tonskihvaljarjev z gladkimi (kovinskimi) oblo -gami ali pa še težji ( v ZDA uporabljajokar valjarje, ki so težji od 15 ton). Vvodo za hlajenje valjev se doda neko -liko sredstva za pomivanje posode, dane pride do sprijemanja z asfaltno zme -sjo. Po navodilih iz literature se valjastatično, čeprav so nam strokovnjaki vPhoenixu povedali, da se tudi vibracijelahko delno uporabijo.

Če je po končanem valjanju površinalep ljiva, se problem reši z rahlim posi -pom peska.

Kontrola kakovostiPri mešanju po suhem postopku jepotrebno nadzorovati granulometričnosestavo vhodnih gumenih delcev, utež -

ni delež gumiranih delcev v masi gumi -rane asfaltne zmesi, predpripravo gu -mi ranih delcev s katalizatorjem in časmešanja v asfaltnem mešalcu. Pri su -hem postopku mešanja vezivo le delnoreagira z gumo, zato ni možno direktnodoločanje lastnosti veziva.

Kontrola kakovosti proizvedene zmesiin vgrajene plasti je enaka kot priklasičnih asfaltnih zmeseh.

Sistem kontrole kakovosti je v ZDA boljdodelan za mokri postopek proizvod -nje, ki ga večinoma uporabljajo, saj jereakcijo med gumenimi delci in bitum -nom lažje nadzorovati.

Gumene delce preiskujejo na vlago(manj kot 0,75%) in določijo speci -fično težo (1,15 ± 0,05). Določijo se -jalno krivuljo - delci ne smejo prese gativelikosti 2,36mm. Vsebnost jekle nihdelcev ne sme biti večja od 0,01 m%,vlaken pa ne sme biti več od 0,5 %.

Preiskave vhodnega bitumna obsegajovizkoznost, penetracijo pri dveh različ -nih pogojih preiskave, zmehčišče inprožnost (resilience test), plamenišče,penetracijo po staranju.

Z gumo modificiran bitumen se preis ku -je z naslednjimi labora torij skimi testi:• penetracija gumibitumna, ki se dela

s konusom; • viskoznost z rotacijskim viskozi -

metrom (v ZDA imajo priročen visko -zimeter za hitre analize);

• prožnost oziroma elastičnost, ki seizvaja podobno kot penetracija,vendar s kroglično konico igle(resilence test);

• zmehčišče s prstan kroglico.

V sami mešalnici pa vsakih nekaj urnadzorujejo viskozimetrom za hitreanalize, še posebej pa pred pričetkomproizvodnje asfaltne zmesi.

Ekskurzija v Phoenix v ArizonoV dneh od 22.3.2010 do 26.3.2010 smobili predstavniki ZAS in proizvajalecasfaltnih zmesi CP Asfalt gostjezdruženja Rubber Pavements Associa -tion (RPA).

RPA je neprofitno združenje, ki je biloosnovano leta 1985, njegovi člani sotako proizvajalci materialov, opreme,vgrajevalci gumiranih asfaltnih zmesikot tudi inštituti in naročniki.

Sprejel in vodil nas je izvršni direktorzdruženja RAP Douglas D. Carlson, kinam je organiziral Asphalt-RubberTech no logy Tour.

Obiskali smo Maricopa County Depart -ment of Transportation (DOT), kjersmo se srečali z g. John Shijem inpred stavnikom Scrap Tire Program Ad -mi nistratiorjem Billom Thorntonom.Gospoda sta predstavila uvodno inpregledno predavanje o arizonskemprojektu Closing the Loop Arizona'swast tire program. Namen projekta jebila organizirana in s pogodbo vezanapredelava odpadnih gum, ki jo sedajizvaja obrat CRM (Crumb RubberManufacturers) za celotno Arizono.Izvedeli smo nekaj zanimivih podatkov,kot npr. letno predelajo okoli 5 milijo -nov ton odpadnih gum s čimer so rešilivelik okoljski problem divjih odla -gališč.

Čeprav segajo začetki uporabe gum všestdeseta leta prejšnjega stoletja (McDonalds) je njihova uporaba postalabolj množična po letu 1990 in od leta1999 se kot obrabna plast na novihcestah uporablja večinoma gumiraniasfalt.


STROKOVNI PRISPEVKI

Merjenje prožnosti gumibitumna(resilience test)

Vhod v Maricopa County Departmentof Transportation


STROKOVNI PRISPEVKI

V nadalje smo obiskali ADOT (ArizonaDepartment of Transportation –Materials Group), kjer smo se pogo -var jali z vodilnim inžinerjem za pro -jektiranje asfaltnih zmesi Ali Zarehomin vodjem laboratorija (ADOT državnilaboratorij, ki nadzoruje kakovost pro -izvedenih in vgrajenih gumiranihasfaltnih zmesi). G. Ali Zareh nam jepredstavil zgodovino od sistema SAMIz uporabo gumenih delcev, do sedajnajveč uporabljenega OGAC asfaltamax. zrnavosti 12,5 za krovne plasti(ARFC), kjer je delež votlin v zmesi cca20-22%v/v. Predstavil je sestave, na -čin kontrole mešanja gumiranih delcevin bitumna v proizvodnji. Ogle dali smosi laboratorij za sprotno kontrolo pri -pravljenega gumibitumna.

Bili smo gostje Federal Highway Admi -nistration AZ Branch, kjer smo sesrečali z g. Kenom Davisom, ki je odgo -voren za nacionalne programe.

G. Davis nam je pripravil predavanje omerjenju in analizah hrupa, še prej pa oupravičenosti vpeljave reciklaže gum vArizoni o potrebah in izrazitem pove -čanju povpraševanja po izvedbi asfal -ter skih del z uporabo gume v urbanemokolju. Glede gumiranega asfalta so zrazličnimi vrstami gumiranih asfaltovznižali hrup od 3 pa celo do 10 dB gledena površino iz bitumenskega betona.Področje Phenixa vodi tako imenovanpilotni projekt, kjer bo poročilo zajelovse faktorje različnih meritev ob vozilu,ob cesti, monitoringe in klimo, hitrostvozil itd.

V naslednjih dneh smo obiskali naj -večje podjetje, ki se ukvarja z vgra je -vanjem gumiranega asfalta, to je FNFConstruction, Inc., kjer nas je sprejelizredno izkušen Mark Belshe. Pred -stavil nam je podatke iz zgodovine raz -voja gumi asfaltov, podatke o mok rempostopku (Wet process or McDonaldPro cess), o potrebi po skrbni pripravi,me šanju (vzdrževanje kon sisten ce) invgrajevanju gumirane as falt ne zmesi vprimernih okoljskih po go jih (nad 10 °C).

V nadalje smo obiskali predelovalnicoavtomobilskih gum CRM, ki je največjav Arizoni.

Avtomobilske gume najprej sortirajo innato primarno drobijo v kose od nekajcm do pribl 10 cm. Ti kosi vsebujejotudi kovinska vlakna in tkanino. Natonadaljujejo z eno linijo pri ambientnempostopku in z drugo linijo po krioge -

nem postopku. Delci gume se nato pre -sejejo v različne granulacije in polnijov big bag vreče po 1000 kg, ki jih povrhu pokrijejo še s črno folijo, da zašči -tijo vsebino pred UV žarki.Bili smo gostje največje državneuniverze za gradbeništvo v Phoenixu,kjer sta nas sprejela prof. dr. KamilKalloush in g. George B. Way, ki ima40 letne izkušnje z asfalti. Sestanek nauniverzi je potekal bolj v stilu razgo -vora, postavljanja vprašanj in debate.

Ogledali smo si laboratorije, kjer izva -jajo predvsem preskuse funkcionalnihlastnosti, kot so utrujanje in togost po4BP (štiri točkovni upogib - imajo dvaaparata avstralske firme ICP), natotriosno ciklično obremenjevanje, za karimajo prav tako dva aparata. Labo -ratorijsko pripravljajo vzorce v valjih zgyratorijem za triosno obremenjevanjein lamele za utrujanje ter togost zzgoščevalnikom, ki so ga razvili sami.

Za zaključek obiska smo se srečali še sproizvajalcem opreme za vmešanje gu -

me v bitumen, z g. Andyem Coxsom naasfaltni bazi v bližini Phoenixa. Priprav -ljali so gumibitumen za vgraje vanje vnočnem času istega dne. Ogle dali smo simobilno mešalnico velike kapacitete, kije sestavljena iz cisterne za vhodni bitu -men, reakcijska komora, kjer se dodajajogumeni delci in mešajo z bitumnom terskladiščne cisterne za gumibitumen.

Strokovno poslovni obisk je bil vrhun -sko organiziran in omogoča dobervpogled v delo in prakso z gumiranimiasfaltnimi zmesmi, kar omogoča pra -vil no delo v naprej, saj se ta tehno -logija uporabe prenaša v Evropo inmogoče tudi v Slovenijo.

ZaključekS prispevkom sem želela predstavitino vo tehnologijo, ki je v ZDA in Azijskihdrža vah že dobro uveljavljena, v evrop -skih državah jo pa še bolj razisku jemoin preskušamo tako mokri kot suhiposto pek proizvodnje. V zadnjem časuje zaslediti vedno več prispevkov o ra zis -kavah na Portugalskem, na Šved skem, vItaliji, v Nemčiji in na Madžar skem.

Vsekakor gre za perspektivno in okoljuprijazno tehnologijo, ki pa ima v vsehsvojih fazah uporabe specifične zah te -ve. Te zahteve je potrebno upošte vati,da bomo lahko uspešno pro izva jali invgrajevali trajni asfalt, ki bo izpol nje -val pričakovanja iz literaturnih podat -kov ter ameriških izkušenj.

Primarno drobljenje odpadnih gum

Odprema vreč z gumenimi delci

Primer reakcijske komore in skla -diščne cisterne za gumibitumen

Udeleženci strokovne ekskurzije

Levo na sliki je prof. dr. Kaloush(ASU), desno D. Carlson (RPA)

mag. Bojana Lukač, Vodja labo ratorija,Zavod za gradbeništvo


IN ENGLISH

To the Asphalt Pavement Association!The insistence on integration, efficientorganisation, and incessant development ofthe Slovenian road construction industry isan imperative of the time, all the more sowhen the conditions of the civil engine eringmanagement and that of the related indu -stries are fierce. We have to take ad van tageof this time to build the necessary foun -dations for the upcoming period of morevigorous investment acti vities. Creatingexpert guidelines and building foundationsthat enable making quality decisions aretherefore a task to be undertaken by allexperts that are involved in developmentand maintenance of traffic routes. This isalso the priority for action of all associa -tions dealing with the issues of design, ma -na gement, construction, and maintenanceof roads and other traffic routes.Education and training has been given a lotof attention in the Asphalt Pavement Asso -ciation since the establishment of this verysuccessful organisation as this was seen asthe only way to reach the aims of itsoperation, i.e. to strive for higher quality

and durability of asphalt products, sustain -able development of technologies, andbigger satisfaction of road users. The resultsof many years of efforts can be seen inroads, in the introduction of severalcutting-edge work procedures, and in theuse of quality materials, which have asignificant contribution to a bigger eco -nomy of investments.The Asphalt Pavement Association has hadsome considerable successes both at homeand internationally. The association encou -rages integration with other societiesinvolved in the road and traffic industries,as well as within the framework of DRSC,Slovenian Roads Agency. Unfortunately,uninformed, generalised, sensationalist,and false assessments of expertise in gene -ral and of the civil engineering industry inparticular found in the media are unfoun -dedly diminishing its successes in the fieldof development of civil enginee ring. Weshall have to fight this with even moredetermination in the future by docu mentingour work, aided by accurate and compre -hensive informing of the general public.The next big opportunity for putting theabovementioned into practice will come atthe 10th Congress on Roads and Traffic to beheld in October in Portorož. The AsphaltPavement Association co-organises this bigmeeting of domestic and internationalexperts. I wish the Association all thesuccess in the future.

Matija VilharCompany Director, DRC

Over the last decades several non-profitcivil associations have been establishedwithin the framework of the engineeringand road construction industry with the aimto organise, connect, promote, and takecare of the development of these industries.These include: road societies in Ljubljana,Maribor, Novo mesto, and the Primorskaregion, DRC - Road and TransportationResearch Association of Slovenia, ZAS -Slovenian Asphalt Pavement Association, as

well as the PIARC National Committee ofSlovenia. These associations were establi -shed on the back of a relatively fast deve -lopment and construction of the road(motorway) network in Slovenia.The Slovenian PIARC National Committeewas established in 1999 as GIZ - a commer -cial association bringing together over 30organisations active in the field roadconstruction, including ministries, roadadministration authorities, research in -stitu tes, and commercial companies. Thenational committee operates in theframework of the World Road Association(PIARC) based in Paris. Over 100 countriesare members of PIARC, many of which haveestablished their national committees. TheSlovenian PIARC National Committee per -forms numerous functions in the field ofroad construction industry, which includeorganising the work of the Slovenianexperts in PIARC technical committees and(co-)organising various events such astechnical committee sessions, panel discus -sions, workshops, and conferences.In April of this year I was elected Chair of theManaging Committee with a 4-year term atthe PIARC National Committee Assembly. Ata time when the cycle of big investments inthe road infrastructure in Slovenia is dra -wing to a close and - solely on the basis ofsome excesses of certain individuals - therehave been attempts at undermining andeven criminalising the efforts of numerousexperts involved in design and constructionof Slovenian roads (motorways), I believethat Slovenian engineers, members of theabovementioned expert associations, needto join forces and constructively stand up tounjust criticism in order to show to theSlovenian public that we have done our workwell, in accordance with the rules, withintegrity, and for the benefit of the country.I hereby vow to actively strive towards thisobjective.

Vili Žavrlan, BEng in Civil EngineeringChair of Managing Committee, PIARC National

Committee of Slovenia

from assembly to Assembly

in English

Maj 2010, leto XIII.

Aktivnosti v preteklem letu (maj 2009 - maj 2010)14. redni letni zbor članov ZAS12. kolokvij o asfaltih in bitumnihIzobraževanje asfalterskega kadraProizvodnja asfaltnih zmesi v letu 2009Intervju s predsednico uprave DARS, Matejo Duhovnik Strokovni prispevki

14.

14th ANNUAL ASSEMBLY OF ZASMEMBERS

The regular annual assembly of ZAS mem -bers was held on 14 May 2009 in DolenjskeToplice. 63 members of the Associationattended.

ZAS Work Report for 2008The report on the work of the Association in2008 was presented by Chairman of ZAS,Slovenko Henigman. Work in the past yearfollowed the guidelines set at the 13thAssembly in Bled, which have remainedbasi cally the same since the establishmentof the Association. ZAS is involved in enab -ling transfer of know-how and flow ofinformation, providing upgrades of techni -cal regulations, enabling networkingamong the asphalt pavement industryoperators, etc. To be able to operate,however, the Association has to take care ofproper organisation and provide the neces -sary funds. Thus, each year ZAS organises anumber of professional meetings andevents, the contents of which havetraditionally been summarised in the annualbulletin, presented to all members of theAssociation. In 2008 the following meetingswere held:• a technical consultation on a very current

issue of guidelines and technicalconditions for laying of asphalt courses,

• a new addition to the programme in theform of the autumn workshop onstructural design, attended also by somedesigners, the foremost goal of which wasto encourage a better quality ofperformance of studies, and

• the 2nd Asphalt Pavement Workers' Dayheld at the end of November

There followed reports by heads of theTechnical and Health, Safety andEnvironment (HSE) Committees.

A short report on the latest work of theTechnical Committee was given by its head,Janez Prosen. Intensive work during thepast year made it necessary for the membersto meet three times. Work was focussed onpublication and explanation of the originalSlovenian standards SIST 1038. Prosen alsopresented some initiatives regardingencouragement of recycling and use of coldasphalt solutions; consideration of andintegration into extended analyses; and theneed for introduction of new measuringequipment and technology.

The basic activities of the HSE Committee,which are mostly related to those of the HSECommittee of EAPA, were presented byAleksander Kerstein. He emphasised theneed for amendment of the edition entitledAsphalts and Environmental Protection withProtection of Workers, which is a joint effortof a group of experts that are hard tocoordinate due to the amount of work they

are involved in. It is thus recommended thata decision be made on whether the bookletshould serve only as an informative guide,or as an accessory. Due to an ever increasingnumber of correspondences in issues andtopics dealt with by the TC and the HSECommittee, Kerstein encouraged jointmeetings, modelled after those at EAPA.

As a conclusion of the report on work donein the past year, Henigman pointed out afew highlights that the year 2008 will beremembered for:• beginning of the ZAS management's new

term of office• record-breaking production of asphalt

mixtures in Slovenia• installation of 1 million tonnes of

asphalts for heaviest traffic loads (almost100 km of new motorways were open fortraffic)

• introduction of new standards: EN 13108and SIST 1038, and preparation of theGuidelines

• publishing activities by ZAS

Considering the above, Henigman conclu -ded that the Association reached all goalsset in the past year and duly thanked themembers for their efforts. He proposed thattherefore the work report be approved,which was met by a round of applause.

ZAS Managing an Supervising CommitteesAt the latest assembly of the Committeemembers a new Managing Committee waselected, comprising of 11 of the most activemembers and representatives of all 9companies active in tier I of ZAS collabo -rations. Due to his leaving the CPM companytheir representative Matjaž Mernik resignedform the Committee. Vasja Grmek of CPMd.d. was elected in his place.

As of this year's Assembly, the term of theZAS Managing Committee comprising ofMari jan Makovec, chair, and Janez Prosenand Miro Žnidaršič, members, also expired.Due to their successful work they weregranted an extension of their term until2012.

Opening addressesParticipants at the Assembly were greetedby the mayor of Dolenjske Toplice, FrancVovk, who expressed his pride in our deci -sion to hold the Assembly there. An espe -cially warm welcome was given to our Chair -man who is a native of Dolenjske Toplice.The mayor congratulated our achievementsin the past and wished us an auspiciousfuture.

The audience also heard an address byMatija Vilhar, Executive Director of the tech -nical field and a driving force of DRC, Roadand Transportation Research Association ofSlovenia. He characterised ZAS as a pillar ofexpertise within the civil engineering

industry. To him the time of economic crisisis an opportunity to make improvementsalso in the field of railway infrastructure,where a lack of adequate staff is felt. Heconcluded his address with an invitation tothe jubilee 10th edition of the Congress onRoads, which is to be held next year inPortorož, and extended his congratulationson our successes.

The last to speak at the Assembly was Mr.Žavrlan, Director of product development atDDC Counselling & Engineering. He alsotouched upon the current recession, noti -cing a decrease of investment within Slove -nia. Given the record-breaking pro ductionof asphalt mixtures in 2008, the fact thatonly 30 % of those were laid in motorwaysinspires optimism. He trusts that ZAS iscompetent in its field of expertise and thatit will continue to work successfully.

Technical Consultation on AsphaltRecycling

Reuse of asphalt milling residue, presentedat the Consultation by Janez Zupan of CPLjubljana and Franz Fegelin of Asfinag, isgaining ever more importance. Developedcountries such as the Netherlands, Ger -many, etc. reuse up to 80 % of old asphalt innew asphalt. In Slovenia we have masteredthe technology of asphalt reuse but it is notas common due to small quantities ofasphalt milling residue. Because of greaterlayer thicknesses, rationalisation, and cost-cutting, this technology is sure to keepgaining ground in the future. Asphaltproducers expect adequate support andawareness from clients as works have to beproperly tendered.

12TH COLLOQUIUM ON ASPHALT AND BITUMEN

The Colloquium on Asphalt and Bitumen isan international meeting of asphalt pave -ment experts, organised biennially by ZAS.As customary it was held at the end ofNovember (26 & 27, 2009) at Hotel Kompasin Kranjska Gora under the general sponsor -ship of Petrol Energy Company and patro -nage of nine other sponsors who had kindlyresponded to the sponsorship invitation.Current recession was evident in the numberof participants; especially missed weredelegates from Croatia and Serbia who werepresent at previous two Colloquiums.Nevertheless, 192 experts attended, 22 ofwhich international. 19 expert papers werepresented and 20 companies exhibited theirproducts.

Prior to the 12th edition of the Colloquiummeetings of ZAS expert committees tookplace. As customary, a meeting of the


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Companies Committee was also held, brin -ging together all representatives of membercompanies. 50 active members of ZAS werepresent. Besides discussions on regulartopics and an overview of ZAS activities, aninternal panel discussion with two guests,Egbert Beuving, Director at EAPA, MaxWeixlbaum, Director at GESTRATA, wasorganised as an opportunity to exchangeviews on topics prepared in advance. We canconclude that the industry has been facingsimilar issues in Slovenia, Austria, as well asthroughout Europe.

On the opening day of the 12th Colloquiumon Asphalt and Bitumen, inaugurated byZAS Chairman Henigman, addresses weregiven by the mayor of Kranjska Gora, JureŽerjav, and the Director of the SlovenianNational Building and Civil EngineeringInstitute, Dr. Andraž Legat. The Colloquiumcontinued with presentations of expertpapers divided in two sections:

• Development of technologies(Moderator: Zvonko Cotič)(Marjan Marolt, Dr. Jochen Holzfeind,Prof. Dr. Johann Litzka, Zvonko Cotič)

• Introduction to SPENS project(Moderator: Mojca Ravnikar Turk)(Mojca Ravnikar Turk, Julijana Jamnik,Mihael Ramšak, Msc, Dr. Stanislav Lenart,Dr. Marjan Tušar)

Thereafter followed technical presentationsand a significant panel discussion entitled»The future of big government investmentsin traffic infrastructure in Slovenia«.Leading representatives of clients, theEngineer and the Controller tried to answerquestions such as: Will the global crisisreally put a stop to planned large infra -structure projects? Where will the gover n -ment find the necessary funds for road andrailway infrastructures? How will theSlovenian civil engineering industry survi -ve? Eminent guests were greeted bySecretary of State Dr. Igor Jakomin whoemphasised, among other things, theimpor tance of Slovenia as a maritimecountry with Port of Koper as its windowinto the world.

The slightly strenuous but instructive daywas rounded up by the singer's MancaIzmajlova velvety voice. She invited to thestage the first speaker of honour, Chairmanof the Slovenian Asphalt Pavement Asso -ciation Slovenko Henigman. All partici pantswere then greeted by Aleksander Svetelšek,Chairman of the Board at Petrol, and RomanDobnikar, Petrol management boardmember. Both expressed their convictionthat ZAS and Petrol have through the yearsformed a reliable partnership throughwhich they have reached many commongoals, and have thus been instru mental inencouraging progress in the asphalt pave -

ment industry. The speeches were conclu -ded by Dr. Peter Gašperšič, acting Director-General at the Road Directorate.

As in the previous years, the SlovenianAsphalt Pavement Association also gaveawards to the most worthy individuals. Thisyear the recipients were two distinguishedexperts. First to be awarded was JanezZupan for his efforts and assistance in thedevelopment of the Slovenian asphaltpavement expertise. Apparently intoxicatedby bituminous fumes in his student years,he found his first job at the Institute forresearch of materials and structures, roadsand insulation section. 15 years later hewent on to Cestno podjetje Ljubljanacontractor where he has remained head oflaboratory to this day. He has stayedfaithful to the asphalt pavement industrythroughout his career, dedicating his exper -tise above all to insurance of quality ofasphalt pavement works. As one of theforemost asphalt experts in Slovenia he has,besides attending to his everyday duties inproduction and quality control, acted as abridge between the Slovenian and Germanindustries. He was a regular guest of variousGerman experts at numerous expert meet -ings. He is also known for his dedica tion totradition and practicality. His biggestachievements are the introduction of SMAmixtures and use of asphalt milling residuein asphalt mixtures in Slovenia.

He has published a considerable number ofexpert opinions and scientific articles andactively participated in ZAS meetings.

The second award went to Feliks Podgoršekfor his valuable contribution to the deve -lopment of the asphalt pavement industryin Slovenia.

Feliks Podgoršek soon found a job whichwas as tailor-made for him. He spent almostthree decades among the leading staff ofproduction and laying of bituminous mix -tures at SCT. Throughout this time he wassuccessful at introducing new technicalknowledge, with the results of his effortsstill visible even today. Podgoršek is anexpert on production facilities and pro -duction of asphalt mixtures, which is why hewas able to, if necessary, lead the pro -duction or deal with deficiencies in ope ra -tion by himself. Despite having retired hestill acts as a valuable consultant to DDCCounselling & Engineering.

In the mature period of his career he be -came known as the foremost expert indetermination of causes of damage. He hadan admirable feeling for introducing newtechnologies and, while working in the Arabworld, was one of the few Slovenians whohad acquired a sufficient knowledge of thelanguage to be able to charm and directlocal supervisors.

In recent years he has strived to improveupon the importance and quality ofinventories of works in the asphalt pave -ment industry.

The second day of the Colloquium sawfurther presentations of expert papers,divided into two sections:

• Technical regulations and modernlaboratory testing methods(Moderator: Egbert Beuving)(Aleksander Ljubič, Dr. Zdravko Ramljak,Dr. Markus Spiegl, Bojana Lukač, Msc, Dr.Janez Žmavc)

• Environmental preservation in theasphalt industry (Moderator: ZvonimirBritovšek)(Dr. Andreja Zupančič Valant, Klaus Graf,Egbert Beuving, Zvonimir Britovšek,Dejan Hribar, Msc)

At the end of the 12th Colloquium on Asp -halt and Bitumen the following conclusionswere drawn:

• New technical regulations, successfullyimplemented together with the certifi -cation, enable safe and stable produc -tion.

• Papers presented at the 12th Colloquiumshowed the prospect of greater use ofasphalt pavements in airports, railroads,and in logistic centres.

• New design regulations have beenaccepted but not yet checked; therefore,we propose a transition period beforetheir final enforcement

• Improvements are needed in projectdesign, inventory of works, and tende -ring processes for pavement works;designers should therefore be enabled togain additional knowledge. It issuggested that workshops are organisedwith the involvement of IZS (SlovenianChamber of Engineers). We are thinkingabout the licensing for the elaboration ofpavement design projects.

• Contracting by the »lowest price« methoddoes not ensure the best results. Pro -posals for more effective and innovativeways of contracting need to be prepared.

• New laboratory tests at high and low tem -pe ra tures have been implemented suc -ces sfully. In the next phase additionaldynamic stiffness and fatigue tests mustbe implemented.

• Use of alternative materials (slag, rubber,lime) and use of reclaimed asphalt are ourfuture. The condition for their use isassurance of the same quality of productas with »new« materials.

• Low noise pavement surfaces are ourobligation. In this field, improvementsand progress is needed. A similar situa -tion is found with low temperatureasphalts, where stagnation in develop -ment has been observed.

• Regular communication with clients anduniversities needs to be established. Whyare we not acquainted with PavementEngineers? How can we encourage thestudy of this field?

• Development of plants and mecha nisa -tion must continue; use of Shuttle Buggyasphalt feeder needs to be encouraged.

• The asphalt industry is aware of theimportance of sustainable development;therefore, measures for lower energyconsumption have been introduced intonew technological processes.

7th EDUCATIONAL CONFERENCE FORASPHALT PAVEMENT OPERATING STAFF

This year's educational conference forasphalt pavement operating staff was heldon 3 March 2010 at Hotel Mons and on thepremises of asphalt plants in Smodinovecand Črnuče, Ljubljana. The programme wasdivided into a theoretical and a practicalpart, conceived in a way to cover all keyissues in the asphalt pavement industry ofinterest to operating staff.

In the first, theoretical part, general topicsof special interest to technical staff werediscussed, ranging from production tolaying of asphalt mixtures. Within thissegment Janez Zupan presented varioustypes and characteristics of asphalt plants,explained marking of asphalt mixtures, anddiscussed production of asphalt mixtureswith emphasis on reuse of mixtures (asphaltmilling residue). Marjan Marolt summarisedthe goals and pointed out the importance ofgood organisation and planning of asphaltworks, which is directly related to thequality of the finished product. The impor -tance of a well prepared engineering siteduring traffic closures and of asphaltfoundation were presented by SebastjanČernigoj. An overview of individual workprocedures ranging from asphalt paving tocompaction of asphalt mixtures, including asummary of the most common errors inthose procedures, was given in detail byIgor Grahek. Jani Planinc gave an overviewof repair procedures and individual tech no -logies suited for various purposes inrenovation of existing roads, which demanda serious and expert approach to deter -mination of causes of damage as well as inthe process of deciding on the type ofrenovation.

The first part concluded with a paper bySlovenko Henigman presenting the conclu -sions drawn from the IARC study focussingon harmfulness of bituminous vapours tothe health of workers in the asphaltindustry. He also summarised the conclu -sions drawn from the 12th Colloquium onAsphalt and Bitumen. He explained to theaudience that bituminous vapours and

aerosols, according to the conclusions ofnumerous international studies, do nothave a harmful effect on human health. Afilm was then shown on the renovation of arunway of the Ljubljana Airport in Brnikperformed in 2009.

The practical part of the educationalconference was divided into four segments.The participants were put in small circlinggroups. On the test field in Smodinovecwork procedures in asphalt mixture layingand paver and leveller calibration werepresented under the guidance of JanezŠuštar. Marko Balkovec presented individualcalibrations and demonstrated the opera -tion of a roller. He also explained pro -cedures in compaction of asphalt mixtures.

The second part took place on the premisesof the Črnuče asphalt plant. Under theguidance of Boštjan Tušar the participantswere shown the plant and presented variousstages of asphalt mixture production. Ro -man Bašelj presented the routine control atthe plant and individual measuring methodsused in internal and third-party controlsduring both production and laying ofasphalt mixtures, bitumen and aggre gates.

The conference was attended by over 130participants from 24 road constructioncompanies who are active members of ZAS.All participants were handed out workingmaterial including a miscellany of lectureabstracts, and the yearly ZAS bulletin. Inconclusion they were also given certificatesof attendance.

The participants were also asked to fill out aquestionnaire; the answers show that thetopics of this year's conference were cur -rent, necessary, and were appropriatelychosen. We will however consider thesuggestion that the conference be done inthe form of discussion rather than lectures. I wish to thank all lecturers and members ofthe organisation committee as well as SCTAsfalti d.o.o. who kindly permitted thepractical part of the conference to be heldon their machines and company premises.

Jožica Cezar

EDUCATIONAL CONFERENCE AT THESLOVENIAN CHAMBER OF ENGINEERS»STRUCTURAL DESIGNING, CONTRAC -TING, AND SUPERVISING OF ASPHALTWORKS«

The Slovenian Chamber of Engineers orga -nised, at our suggestion, an educa tionalconference for all designers, clients, andsupervisors in order to acquaint them withnew technologies in the asphalt industry, newstandards that were publi shed in 2008 andinclude new markings of asphalt mixtures,and new inventories of works for structuraldesign and contracting of asphalt works.

The following papers were presented:• European and Slovenian national stan -

dards for asphalts (Aleksander Ljubič)• Initial testing and quality control,

including guidelines and technicalconditions for construction of asphaltcourses (Aleksander Ljubič)

• Introducing standards into practice -Practical examples (Zvonko Cotič)

• New technologies and materials in theasphalt pavement industry (Zvonko Cotič)

The conference was held on 27 January2010 on the premises of the SlovenianChamber of Engineers in Ljubljana. 55participants attended.

PRODUCTION AND CASTING OFASPHALT MIXTURES IN 2009

In 2009, 2.3 million tonnes of hot asphaltmixtures were produced in Slovenia.

For the mixtures produced, approximately2.117 million tonnes of carbonate aggre -gate mixtures, 405 000 tonnes of silicateaggregate mixtures, and 115 000 tonnes ofbituminous binders were used. The portionof cast road bitumens amounted to 70 000tonnes, while a good 15 000 tonnes ofpolymer-modified bitumens were also cast.The percentage of modified bitumen withinall bitumen used was 18 %, equalling that in2009.


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In 2009, beside other asphalts, 143 000tonnes of SMA, 136 000 tonnes of AC bin,714 000 tonnes of AC surf, and 1 213 000tonnes of AC base asphalts were producedand cast in Slovenia, the portion of porousasphalt mixtures amounting to appro -ximately 5 200 tonnes.

COLLABORATION WITH OTHER ASSO -CIATIONS (EAPA, GESTRATA, DRC, etc.)

ZAS has been a member of EAPA since asearly as 1997. Our representatives areinvolved in all EAPA bodies (Board ofDirectors, Technical Committee, HSE Com -mittee), which ensures the flow ofinformation into Slovenia.

The Slovenian and Austrian Asphalt Pave -ment Associations have formed an excellentcollaborative partnership over the last 15years. Besides participating in each other'smeetings and other activities, there is atradition of visits of senior representativesof clients and contractors in either inAustria or in Slovenia. More than 200exchan ges have taken place until now.Tradition calls for the next visit to comefrom our side, so we will try to schedule itfor the beginning of July 2010.

We have been meeting with our Germancolleagues primarily during each country'sbiggest meetings, in Kranjska Gora andBerchtesgaden, respectively. This was thecase this year as well, when several DAVrepresentatives attended the 12th Collo -quium on Asphalt and Bitumen, whileSlovenian representatives participated inthe XV. Deutsche Asphalttage. The extre -mely well organised meeting of the asphaltpavement industry experts has indicatedthe scope of the contribution roads canmake to the solution of the economic crisis.Apart from extensive funds intended forrenovation (up to 2 % of the value of allinvestments per year), Germany intends toallocate as much as 50 billion Euros forinvest ments into 1 900 km of new motor -ways and 2 200 km of existing motorwaysto be widened it the period up to 2015.

10th SLOVENIAN CONGRESS ON ROADSAND TRAFFIC 21 - 23 OCTOBER 2010

The 10th edition of the Slovenian Congresson Roads and Traffic will be held on 21 - 23October 2010 at Grand Hotel Bernardin inPortorož.

The organising committee will release amiscellany of expert papers and a CD. Twobooks will also be published on this occa -sion: on road maintenance and Slove nianroads through time.

Important dates:

23 December 2009Invitation to authors to submit papers

31 March 2010Submission of papers, drafts, and abstracts

1 July 2010Submission of full papers

10 September 2010Programme and Invitation to the Congress

9 October 2010Early Registration Period – lower participantfee

18 October 2010Registration Deadline – higher participantfee

20 October 2010Congress Programme – 3rd notification

FUNCTIONING OF THE ASSOCIATION'SBODIES IN 2009

Managing Committee (MC)MC members met on 6 occasions in theperiod since the last Assembly, all of whichachieved a quorum as an 80 % attendancewas recorded. 36 resolutions were passedwhich were entirely realised.

Beside the 11 members of MC the sessionswere also attended by Marjan Makovec,Chair of Supervising Committee, Head of theTechnical Committee Janez Prosen, JožicaCezar, and Zvone Cotič.

MC is the driving force of the Association asits sessions cover all pertinent issues.

Technical Committee (TO)Activities of the Technical Committee over along period show that the current issues oftechnical regulations and European as wellas Slovenian regulations are followed. Workin 2009 was focussed on implementation ofthe published original Slovenian standardsSIST series 1038. Discussions were centredaround the adequacy of their contents andof the selected categories of properties.Initiatives have been given, the documentsare open to amendment, and the Technical

Committee, following the current practicalfindings, considered the technical regula -tions from the perspective of the con clu -sions drawn from the Asphalt Committee'soperational meetings as well.

The work of the Technical Committee hasincluded discussion on the incentive to con -trol the procedure of certification in asphaltpro duction plants as stated in the Construc -tion Product Directive (CPD). The relevantprocedures were introduced fairly smoothly,aided by a large-scale activity of theCommittee, involving meetings of therepresentatives of asphalt manufacturersand intensive dialogue with control ser vices.

The work of the Committee had a substantialimpact on the high degree of surveillance ofquality control as there is a considerableemphasis on interlaboratory tests. In 2009a constructive critical discussion was faci -litated on control of properties of bothinput materials and produced mixtures, aswell as laying. The Committee was led intheir work by the question of how quality iscontrolled. Regarding materials, especiallybituminous binders, there was a call forextended testing and determination of thetemperature range of binders in use (PG).

The sustainability aspect of pavementcondition was pointed out. There has beenan initiative to control functional propertiesof asphalt mixtures and layers, which meansthat the work of the Committee will be alsodedicated to so called extended testing,which we have called »dynamic testing«.

Europe has gravitated towards preservationof natural resources and protection of theenvironment. The requirements of the socalled environmental protection directiveshave been coming into the foreground,dictating to an ever larger extent theexploitation of existing resources. Reuse ofasphalt has been vigorously discussedwithin the Committee and is highly encou -raged. The topic was highlighted bypresentations made by members of theTechnical Committee in the framework ofthe past year's Assembly.

In their meetings in 2009 the TechnicalCommittee has also discussed cold asphalts,summarised the information from the pastyears, and outlined future goals.

In contents and topics, the work of theCommittee followed that of TC EAPA, whichpromotes and brings together the interestsof the asphalt pavement industry within theEU. These include, as stated above, sustai -nability, conservation of resources, worksafety, and environmental protection. TheCommittee has been collaborating on thesetopics with the ZAS Health, Safety, andEnvironment Committee. Through its TC,the EAPA has published a number of

documents with the aim to promoteunderstanding and awareness, andencourage sustainable thin king inconnection with asphalt, which is the singlemost common construction material usedin road infrastructure all over the world.Encouraged by TC EAPA we plan to prepare adocument on recycling of bituminousmaterials modelled after the existingpublication on recycling of con crete. Thetask has been embarked upon by the ZASTechnical Committee and will continue tobe discussed in future meetings.

Discussions during the two main meetingsin June and November of 2009 have shownthat the work of the Technical Committee iscentred on assisting control services, asp -halt producers, investors, surveillanceservices, and contractors. It is a way ofsystematic exchange of opinion, exhibitingthe power of integration and promotion ofawareness.

The work of the Committee provides infor -mation on current happenings in the tech -nical and operational fields in Slovenia andfurther afield. A proposal has been given tomake the information available through theZAS portal. It is evident that we do not inany way lag behind the developed countriesof the world.

In 2009 the Committee has discussed regu -lar monitoring of asphalt as the mate rial ofthe upper structures of pave ments and out -lined its future course. We have been expan -ding our initiative, given the year before, thatpavement engineers become better acqu -ainted with basic characteristics of asphalt.

I can conclude that in 2009 the activities ofthe ZAS Technical Committee were perfor -med systematically, with a goal to pro videintegrated information to strengthen tech -nical knowledge of asphalt. I would like tosincerely thank all who took part in our workand invite them to continue their efforts inintegration in the future.

Janez Prosen

HSE CommitteeAction policies:

WORKERS' HEALTH – SAFETY OF WORKERS inproduction, casting/laying of asphalt mix -tures, waterproofing works, and other workinvolving bituminous products. Specialattention is given to protection of workersexposed to traffic and protection of othertraffic participants.

ENVIRONMENTAL PROTECTION focuses onprevention and reduction of burden to theenvironment during production, laying, andoverall work with bituminous products.These are achieved by reducing emissionsinto the atmosphere, water, and soil,diffuse emissions and immissions.

It is equally important to try to decrease CO2

production and its emission into the en -viron ment.

Attention has also been given to reductionof energy consumption and use of rene -wable energy sources.

In the 2009/10 period the Committee meton two occasions, in November 2009 andMay 2010.

In both meetings the following topics andissues were discussed:• information about environmental protec -

tion projects in the EU that involve theasphalt pavement industry

• information on the progress of REACHproject

• conclusions drawn from the IARC study• agreement on a new way of operation of

the Committee in order to attain a higheractivity and participation of all membersof the Committee: individual members ofthe Committee shall be put in charge oftopics which shall – as scheduled oraccor ding to relevance – be presented tothe Committee, with the recommendationthat internet communication with theother members be used beforehand

• Recycling (cold and hot) of asphalts fromthe perspective of protection of theenvironment and workers in their workingenvironment (exposure of workers toasphalt mixture fumes)

• Low temperature asphalts: this previouslyhot topic in the asphalt pavementindustry has recently taken a back seat.The aims to reduce energy consumptionand fumes can surely be reached thoughlow temperature asphalts. The conc -lusions drawn from the IARC study reducethe need for low temperature asphalts,which are more expensive, and contrac -ting authorities are unwilling to cover thedifference in cost

• Discussion on approaches in asphaltplan ts in Slovenia according to Article 7of the Regulation concerning emissionsfrom asphalt mixture production plants

• Information on new technologies, suchas the use of rubberised asphalt throughthe use of rubberised bitumen. Thistechnology has a great perspective due tonot only its technical, but also environ -mental characteristics, especially fromthe viewpoint of traffic noise reduction.This is a very current topic in the EU aswell

• On both meetings information was pro -vided on current activities in the EAPA

Aleksander Kerstein

Waterproofing SectionMembers of the Waterproofing Section meton a single occasion since the latest ZASAssembly.

The interlaboratory comparative analysis ofbituminous adhesives has been completed,

which comprised of a collaboration of fivelaboratories analysing adhesives by threedifferent manufacturers, and the laboratoryat the Graz technical University, whichperformed additional measurements ofshear strength. The results of the compa -rative analysis will be analysed in detail bythe Section's members at the next meeting.

Highlights of the 2010 work programmeinclude:• discussion on material characteristics

and methods of horizontal waterproofing• monitoring of developments in

legislation in the field of bituminousmaterials

• propagation of knowledge among users

My sincere thanks go to my colleagues andto all who have supported the work of theSection. I hope for a successful futurecooperation.

Olga Naglič

Education SectionEducation of asphalt pavement staff is themost important task of the Association co-ordinated by the Education Section. Pro -gram mes are prepared for each year basedon current issues in the industry. A draftprogramme that is put up for discussion isprepared in November of the previous yearand presented at the meeting of theCompanies Committee, which usually occursduring the Colloquium on Asphalt andBitumen or the Asphalt Pavement Days.

There is an educational conference forasphalt pavement staff scheduled for eachyear, namely alternately for technicalworkers and for training of operationalstaff. Target groups of each conference arenot strictly separate which means that notfew engineers participate in the operationalstaff trainings; this is very practical fromtheir point of view, while it is proof for usthat we are keeping the level high enoughfor all profiles of asphalt pavement staff.

When organising educational conferenceswe are aware of the significance of practicaldemonstrations; consequently, we do themin two separate parts, a theoretical and apractical one, where participants have theopportunity to point out difficulties theyhave encountered and to exchange opinionsand experience.

The conferences for technical staff haveusually been organised centrally in Ljub -ljana, while this year a practical training ofoperational staff (in a training area, in anasphalt plant, and in a laboratory, withsmall size groups) was organised inLjubljana as well for the first time.

When choosing topics of lectures, needs andcurrent state of affairs in the industry aretaken into consideration. We try to inform


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the participants of new developments in thefields of technical regulations, laboratorytests and equipment, production, casting,and compaction of asphalt mixtures, tech -nological procedures of renovation, as wellas safety of workers and protection of theenvironment as they come along. Inaddition to organising the annual confe ren -ces, we are involved in preparation ofprofessional meetings and other events, aswell as panel discussions, workshops, andseminars, as needed. Invited lecturers areusually experts from the industry, activemembers of our association, who also helpprepare work material.

All members of the Education Sectionconvene once a year at a meeting whereguidelines for decisions of the ManagingCommittee are prepared. Our organisationalcommittee meets with lecturers prior to theconferences as needed.

It is of key importance for the quality ofwork of the Section that all involved in theprocess participate in selection of requiredtopics. Your initiatives, opinions, andwillingness to cooperate are very welcome.We shall endeavour to stay true to yourexpectations.

We also welcome feedback from the partici -pants and would like to kindly inviteeveryone to fill out the provided question -naire.

I would like to thank all members of theSection for their cooperation and wish forequally successful collaboration in thefuture.

Jožica Cezar, MSc

Asphalt CommitteeIn the past year the Committee was activelyinvolved in preparation of guidelines forlaying of asphalt mixtures, conceived andcoordinated by Dr. Janez Žmavc. After 12amendments and harmonisations theguide lines were published under the title ofTSC 06.300/06.410 SMERNICE IN TEHNIČNIPOGOJI ZA GRADITEV ASFALTNIH PLASTI(Guidelines and Technical conditions forBuilding of Asphalt Layers) in the OfficialGazette of the Republic of Slovenia, No. 65,issued on 14 August 2009.

TSC 06.300/06.410 is a technical speci fica -tion for public roads whose use is optio nalbut is a requirement of tender speci ficationsfor construction and main tenance of roadsin the Republic of Slovenia. The docu mentalso covers designing – in addition to laying–, as inventories of works are a componentpart of the Guidelines.

The Commission met on three occasions in2009 and adopted a number of decisions.Besides the Guidelines the Commission wasactively involved in the issues regarding the

use of black furnace slag in manufacture ofwearing asphalt courses for heaviest trafficloads and those regarding addition ofasphalt aggregate (milling residue) tobituminous mixtures for bearing asphaltcourses for heaviest traffic loads. TheCommittee supported the decision to set upa test field for slag and approved the use ofmilling residue in the subbase of AC 32 basefor all roads, including those subjected tothe heaviest traffic loads. Unfortunatelythe contracting authority would not agreeto such use, mostly due to being under -informed about the possibilities of reuse ofasphalt.

To this end we organised in September anexpert exchange with our Austrian collea -gues from the Asfinag motorway companyof Graz. The Slovenian delegates who wereacquainted with the use of recycled asphaltin Austrian motorways came form thefollowing institutions: DARS, DDC, ZAG,Igmat, and Primorje.

One of the participants was Andrej Vovk,BSc in Civil Engineering, coordinator formain tenance at DARS, who added to thesuccess of the visit with his customarilyintelligent insights, questions, and re -marks. Sadly, as of 31 January 2010, he isno longer with us. He is sorely missed.

The Asphalt Committee is a professionalbody established by DARS in 1995. In the 15years of its operation the Committee, whichhas met on 74 sessions, has seen many trialsand tribulations. The dictate of the times isforcing the Committee to widen its scope ofactivities to include state roads; its futurechallenges thus include:• noise reduction,• improvement of pavement evenness, and• higher durability of pavements.

All this among constant increase of trafficload.

Slovenko Henigman

Supervising Committee (NO)The Committee, comprising of MarijanMako vec, Head, and Janez Prosen and MiroŽnidaršič, members, met on 7 April 2010,immediately before the latest session of theManaging Committee. Upon examination ofall financial statements and accountingrecords the Committee gave a favourableopinion of the reviewed annual accounts for2009, which are to be confirmed at thisyear's ZAS Assembly.

EXPERT PAPERS

PAVEMENTS IN MOTORWAYS AND TUNNELS – ASPHALT OR CONCRETE?

IntroductionWith the opening for traffic of the motorway

sections past Maribor and across Rebernicein the week of 10 - 15 August 2009, the bulkof the national motorway construction cameto a close. The time has now come to makein-depth economical, technical, sociolo gi -cal, and other analyses in order to evaluatethe success of the largest infra structureproject in Slovenia to date. Was it in fact tooexpensive and too time-con su ming as themedia is lately so fond of poin t ing out? Otherprojects like it will be lunched, since thenational development documents foreseeadditional investment in the road andrailway infrastructures, energy industry,creation of commercial centres, etc. Theseinvestments are necessary and will be themotor of Slovenia's economic development.

Comments regarding the construction of themotorway programme made in recent yearshave all too often painted a decidedly nega -tive picture. With the programme nowcompleted, it seems as if hardly anybody iscontent with the constructed motorways.

Recently, many professional dilemmas havebeen expressed in public that for the mostpart were left begging for adequately infor -med answers. I could even go as far as to saythat, without fully supported reaso ning, theopinion has prevailed that every thing isamiss.

Thus the dilemma has surfaced again by endof 2009 regar ding the type of pavementsurfaces in our tunnels – should they beconcrete or asphalt? We have beensubjected to all sorts of opinions, even suchcontaining inade quate information or plainmisinfor mation as to why asphalt is not fitfor use in tunnels as it is combustible andless durable as opposed to cement concrete.

In this paper I would like to expose certaindilemmas which occurred during construc -tion and explain the reasoning behind ourchoices for individual solutions in theprocess of pavement construction on mo -tor ways.

How it all beganThe beginning of motorway construction in1993 and the first National Programme ofMotorway Construction in the Republic ofSlovenia was marked by a sense of pride,positive energy, and superlatives. The scopeof motorways constructed up to then wasfar too small to be able to provide thenecessary mobility and flow of road traffic.

The first motorway section to be openedwas Čebulovica – Divača on 12 July 1995,follo wed by others. A successful financingmodel was created, as were models ofsubcontracting, construction, inspection,and quality control. The slogan »Slovenia isConstructing Motorways« was introducedand the wheels of DARS, Motorway Companyin the Republic of Slovenia, headed by their

first Chairman of the Board, were set inmotion. Many thousands of designers,techno logists, direct contractors, surve -yors, and suppliers were involved in theconstruction of Slovenian motorways.

It is only natural with such an extensive andlong-running project that some excesseswere noted which, however, cannot mar thesuccess of the realisation of set goals ordeny the work of numerous experts involvedin the project. Therefore I would adviseagainst overgeneralising things.

Most of those involved performed theirduties successfully and with a sense of duty.The first goal of the experts who dealt withpavements was to eliminate rutting (Photo1) from the Slovenian motorways, whichwas quite extensive. The rutting present wasa hazard to traffic safety an affected drivingcomfort. In-depth professional work indevelopment and research, and collabo ra -tion among local experts and with inter -national ones, who provided the asphaltindustry with valuable advice, facilitatedquality execution of Slovenia’s pavementsas they are today. To this end numerouslaboratory testing methods were introducedamong other measures (Photo 2).

Photo 1 (on page 24): Rutting on theVrhnika – Logatec motorway sectionpavement in 1993

Photo 2 (on page 25): Low and hightemperature resistance tests performed onasphalt courses

Motorway PavementsPavement is the finishing of a road,consisting of various courses of bound andunbound materials, on which traffic flows.Bound courses include finishing layers ofasphalt or cement concrete. Because this isthe uppermost layer subjected to traffic, forwhich roads are intended, it is one of thekey elements of a road. The pavement, fini -shed with a pavement surface, is the factorthat affects traffic safety, driving comfort,noise, and service life of a road.

Photo 3 (on page 25): Typical »half rigid«Motorway pavement in Slovenia

In some countries where (cement) concreteand asphalt technologies of pavementconstruction are similarly well developed,both are the subject of fierce competitionbetween pressure groups, as each has itsadvantages and shortcomings. In Sloveniaas well, we faced a dilemma as to whichtechnology to choose before the start ofintensive motorway construction. A specialstudy made by the former Cestni inženiring(now DDC) favoured concrete due to itsmechanical characteristics and durability.

At that time there were at least 10 domestic

companies with a firm grip on asphalttechnology, while there were none whocould without hesitation claim that forconcrete technology. Concrete slabtechnology is more demanding than asphalttechnology from the perspective of logisticsas well. Traffic loads 15 years ago are hardlycomparable to those today. Very fewmotorway sections saw more than 1000heavy trucks a day. Traffic studies made forthe period of the next 20 years, which at thetime were the basis for deciding on asphaltpavements, did not foresee today’s circum -stances.

As a rule, asphalt pavements provide morecomfort to the user, are less noisy, andenable easier upgrading (strengthening)and maintenance (e.g. patching). On theother hand the advantages of concretepave ments include lighter pavement sur -face, stability (undeformability), and as aconsequence, higher durability. The latteralso results from their thickness, whichmust be at least 24 or 25 cm in concretepavements. Asphalt pavements are thinner,17 to 23 cm on Slovenian motorways, in afew cases even less. Consequently, asphaltpavements are also more competitive asthey are less expensive.

Due to the above, no real rivalry existsbetween the two competing technologies inSlovenia. The expert opinion favoursconcrete pavements, which in a wayrepresent an alternative when extremeloading is involved.

Skid characteristics in both types ofpavements depend on the type of materialused. Lately, silicate (eruptive) rock hasbeen used almost exclusively for bothasphalt and concrete pavements, i.e. forgrain sizes over 2 mm, as it ensures a moredurable skid resistance due to its highresistance to polishing. Previously, stonematerials consisting of roughly 50 % ofsilicate grains and 50 % of carbonate grainswere used in both types of pavements. Eventhough these do not give a superlative levelof skid resistance, they do ensure a higherdurability of mixtures. The main reason fortheir use was the fact that on one hand theylent an adequate quality of pavement andon the other, more affordable domesticstone materials could be used, namelylimestone, while eruptive rock is mostlyimported from Austria or Croatia.

After 2000 DARS introduced a system ofpermanent measurements of the state ofpavements as a part of the PMS (PavementManagement System), on the basis of whichrenovation measures are determined.Measurements performed in 2005 based onthis Swiss-Canadian system, introduced inSlovenia and adapted to our conditions byDDC Counselling & Engineering, showedthat the quality of skid resistance of

pavement surfaces in tunnels was inferior tothat in open surfaces. Under thesestandards traffic safety was jeopardisedand immediate renovation of polishedpavements was suggested. The issue wasoverblown by the media and caused theinfamous public scandal of the supposedlyskid-prone pavement surfaces in the Trojaneand other tunnels.

In these tunnels the exorbitant growth ofespecially heavy traffic in connection withthe specific conditions in tunnels causedunexpectedly rapid polishing of pavementsurfaces. These had been treated with juteafter construction, which failed to allowsome 50 % of the stone grains to protrudefrom the surface. Subsequent milling of thesurface, performed last year, enabledelimination of cement wash from thesurface and ensured the presence of erup -tive rock grains, which provide adequatemicro and macro roughness. Thus adequateskid resistance has been ensured in theroughened pavement surfaces in all of thesetunnels. Measurements are taken regularly.No significant deterioration of skidresistance was detected in the first yearafter the treatment, which goes to provethat the fault for inadequately executedconcrete pavement surfaces lies chiefly inan inappropriate treatment of surfaces withjute. In subsequent construction the por -tion of eruptive rock aggregates was signifi -cantly increased, from 50 % to e.g. 75 %, toimprove skid resistance even further.

Construction of concrete pavements in theTrojane tunnels was done according to theknowledge we possessed at the time andthat was very similar to the knowledge inthose European countries that build conc -rete roads (Germany, Austria, Switzer land,and Belgium), where they also roug henthem as needed. Current execution ofconcrete pavements has remedied theshort comings that had been identified.Thus, there is no reason to avoid buildingroads with cement concrete pavements.

Traffic Loads on MotorwaysRoad traffic is represented by annualaverage daily traffic, or AADT, of all vehiclesand by traffic load (TL). For the latter, theimpact of vehicles from their mass andnumber of axles is converted to the count ofhow many times the nominal axial load of 82kN (8.20 tonnes) or 100 kN (10 tonnes) asexceeded. Traffic load is affected primarilyby cargo vehicles. The amount of traffic(AADT) affects fluidity of a road while largetraffic loads mainly cause fatigue, i.e.infrastructure damage. In the designingstage a separate traffic study is done foreach individual section, predicting theextent, structure, and growth of traffic for aperiod of 20 years. Studies performed in thepast 15 years have proved to be veryaccurate as far as AADT is concerned. On the


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other hand, there were major discrepanciesin TL predictions. All TL studies predicted a 3to 4 % yearly growth, while in reality thiswas 4 to 5 times larger on some motorwaysections over the past 10 years (i.e. between16 and 17 % per year (Figure 1)). This is anextremely high discrepancy, which can beattributed to a number of factors, such asmany new countries entering the EU,extraordinary economic growth in Sloveniaover the past few years, completion ofindividual highway routs, etc.

Figure 1 (on page 26): Average yearly growthrate by vehicle type and motorway route forthe 1998 – 2008 period

With the increase of traffic load, which ismostly attributed to an enormous surge inthe number of heavy trucks and towingvehicles (from 1000 to 5000 vehicles perday), Slovenia has jumped several classesand has approached the traffic load of thehighly developed European countries. Thishas of course exhibited a significant effecton roads and especially pavements, whichhad been designed for much smallerexpected traffic loads. Therefore numerousinterventions and renovation works on theexisting motorways, which include resur -facing and, in general, the necessarystrengthe ning as well, must not surprise us.These measures are determined by theaforementioned PMS, which is based on theprinciple of optimising costs and benefitsfor users and the administrator.

2009 was the first time in many years that adecrease of traffic load was registered,excepting the Pomurje motorway route,amounting to up to 12 % on some motorwayroutes.

Figure 2 (on page 26): Average daily numberof trailer vehicles in a year by motorway routefor the 1998 – 2008 period

Asphalt or Concrete in TunnelsDisregarding the fact that mainly asphaltroads have been built on motorways, adecision was made at the beginning of themotorway construction programme to startbuilding concrete pavements in specialconditions. The first of these special caseswere the Golo Rebro and Pletovarje tunnelsin the Štajerska region and the Tabor tunnelin Primorska, executed by SCT with a rentedGerman concrete paver. After that, follow -ing the 1999 adoption of a policy to buildconcrete pavements on tolling stations anddeceleration lanes in addition to tunnels,SCT have acquired the required paver andbegan executing these works indepen -dently. Other contractors did not decide onacquiring such equipment as they had appa -rently determined that there would not beenough of such work. In fact, over the last10 years only the Trojane, Dekani, andKastelec tunnels were built in concrete, plus

around 10 km of deceleration lanes andsome tolling stations, totalling around 30km (or 2 %) compared to almost 1500 km ofone-way carriageways on motorways. Withsuch a limited extent of works, developmentis, of course, restricted; on the other hand,contrary to a number of European countries,including for example Italy, France or Croa -tia that eschew concrete altogether, Slo -venia builds and develops concrete roads.

The main reason behind the decision to buildconcrete pavements in tunnels was the lightcolour of their surface. Other rea sonscommonly mentioned in public, such ashigher durability and non-combu stibili ty,are incorrect and can often be misleading.

Asphalt is a mixture of rock material, stonedust, and bitumen. As an oil productbitumen is combustible; however, withinasphalt it is combined with stone dust toyield bitumen mortar, which preventscombustion, making arguments about itscombustibility groundless. Due to severaloccurrences of fires in tunnels in the Alpineregion in 1999 and 2005 many studies andanalyses were performed on the subject. Acomparison was done between the use ofasphalt and concrete in tunnels. A specialstudy was undertaken by the PIARC C5Technical Committee, the so called RoadTunnels Committee. The conclusions drawnfrom the study are the following: »It isevident from all documented studies thatthe use of asphalt as road constructionmaterial in tunnels does not have asignificant effect on the scope and degreeof fire. Pavements made of asphalt do nothave a significant effect on safety in case offire and can be used in tunnels.«Furthermore, in tunnels stable weatherconditions are observed (there are no signi -ficant temperature fluctuations), which,given similar thickness, ensure a fairlycomparable service life of asphalt as com -pared to concrete. The only crucial drawbackof asphalt is therefore its darker colour ofpavement surface. This can be remedied byincreased lighting, while light asphalts,which make use of lighter aggre gates andsynthetic binders, can also be used.

Skid characteristics of pavement surfacesdepend on the rock material used. Intunnels these are inferior in any case,regardless of the type of pavement surface,which appears to be mainly due to differentconditions from those in open routes, whichare subjected to weather (see Asphaltpavements in tunnels report by EAPA). Dust,soot, and tyre residues accumulate onpavement surfaces in tunnels, necessitatingregular washing and cleaning of bothconcrete and asphalt surfaces.

Photo 4 (on page 27): Concrete surface in theGolovec tunnel and of a deceleration lane onthe Klanec – Srmin motorway section, 2004

In European countries several hundred kilo -metres of pavement surfaces in tunnels aredone in asphalt, the longest being theLaerdal stunnel (l = 24510 m) in Norway,Tou lon (l = 3200 m) in France, crossing ofthe Elbe (3543 m) and A71 near Suhl(7900 m) in Germany, the Oresund tunnel(3510 m) in Denmark, the Westerschelde -tunnel (6600 m) in the Netherlands, etc.

Photo 5 (on page 27): Asphalt surface in theLeščevje tunnel on the Dolenjska motorwayroute, 2008

ConclusionThe basic motorway programme is nearingits completion. The motorways performtheir function well, carrying tens ofthousands of users each day.

If in 1993 numerous asphalt roads InSlovenia deformed by rutting were a causefor concern, this has now been eliminateddespite the sharp increase of traffic load.Pavements are of adequate quality, en suringproper traffic safety and ride comfort.

The extent of construction of concrete roadsin the past did not allow the necessarydevelopment; nevertheless, we have maste -red the technology in Slovenia. Extremetraffic loads over the past 10 years haveshown the need for additionally strengt -hened asphalt pavement construc tion.International experience has demonstratedthat even though traffic load can tempo -rarily decrease, as was the case in 2009, itsoon reverts to its previous condition andstarts growing again.

Thus in road tunnels, asphalt and concretepavement constructions have been on par.In both cases appropriate cleaning ofpavement surfaces (high pressure washing)must be ensured to provide adequate skidcharacteristics and traffic safety.

Slovenko HenigmanManaging Director for MotorwaysDDC Consulting & Engineering Ltd

Sources:• EAPA, »Asphalt pavements in tunnels«,

May 2008• DDC Counselling & Engineering internal

documents

EXPERT PAPERS

RUBBERISED ASPHALT MIXTURES

IntroductionMillions of motor vehicle tyres are discardedeach year, including those from cargovehicles. In Slovenia alone, according to thedata provided by the Statistical Office of theRepublic of Slovenia, up to 18 000 tonnes ofscrap tyres a year have been collected in

recent years. More than half of the collectedtyres are combusted as fuel in the cementindustry, which makes a significant contri -bution to the CO2 emissions in Slovenia.Less than half of the tyres are processed inone way or another. I have thus far not comeacross a Slovenian processor who couldmake rubber scrap available for use inasphalt mixtures.

There are several methods available forprocessing tyres into reusable products.One of them is crushing tyres into crumbswhich are then used for modification ofbitumen. Research in the field is quitepromising and anticipates a beneficialsolution for the large quantities of collectedscrap tyres and development of moredurable asphalt courses.

The addition of crumb rubber to bitumenimproves its performance-related qualities.Asphalt mixtures made with rubberisedbitumen are more stable and more elasticand thus have a higher resistance to defor -mation in comparison to similar mix turesusing conventional bitumen.

They exhibit a higher resistance to extremetemperatures, i.e. high temperatures,which makes them more resistant torutting, and low temperatures, which makesthem less prone to cracking. Furthermore,they have a higher resistance to changesdue to ageing of bituminous binder. Thismeans that resistance of asphalt courses tofatigue is improved, contributing to theirhigher durability.

Due to elasticity of rubberised asphalt cour -ses motor vehicle tyre wear is diminished.

When appropriately chosen, rubberised as -phalt mixtures can aid considerably in thereduction of noise resulting from asphaltsurfaces.

Rubberised asphalt overlays reduce damagethat arises from lower layers of asphalt.

The surface of rubberised asphalt retains itsblack colour longer, enabling a highertransparency of colour road markings.

Experts in the field of rubberised asphaltmixtures and courses emphasise that pro -duction of rubberised asphalt mixtures is infact more expensive than that of conven -tional types, but the thinner layers of suchasphalts make for much cheaper mainte -nance.

Materials

BitumenThe chemical composition of bitumen is verycomplex, including many different organiccompounds that seldom allow precise iden -ti fication due to a high degree of mutual

correspondences. The composition variesaccording to the source of oil and therefining process involved. Chemical com po -sition of bitumen and temperature have agreat impact on mechanical properties andmicrostructure of bitumen. As input bitu -men road bitumen adapted to climaticconditions and the purpose of use is used.

Crumb rubberThe rubber mixture used in tyre productioncombines natural and synthetic rubber(most often styrene-butadiene rubber, orSBR), various petroleum products, che -micals, and soot. To improve its service lifeand retain flexibility, optimised wax,antioxidant, and antiozonat mixtures areadded.

Crumb rubber (rubber particles) is obtainedfrom scrap tyres using the following twomethods: grinding at ambient temperature(ambient process), where scrap rubber ismilled, and cryogenic method, where rub -ber chips are frozen using liquid nitrogenand ground into fine particles. During bothprocesses metal particles are removed (wireresidues from magnet crushing), as aretextile particles (by blowing). Both proces -ses yield particles of similar size, yetdiffering in surface characteristics.

Photo 1 (on page 28): Ambient processPhoto 2 (on page 28): Cryogenic process

For bitumen modification particles obtai -ned using the ambient process are used dueto their reactive surface.

One tonne of scrap tyres yields 400 – 700 kgof crumb rubber and 150 – 250 kg of scrapsteel, which can also be reused. The rest isunusable waste.

Rubber particles are marked as CRM (crumbrubber modifier), as their use modifies theproperties of hot asphalt mixtures andcourses.

AdditivesThe additives used in the production ofrubber modified bitumen include lime,polyphosphoric acid, and amines, depen -ding on the purpose of use of the asphaltmixture containing such bitumen. Each ofthese additives affects the properties ofrubber modified bitumen in a different way.

Preparation of rubber modified bitumen(RMB)Thus far there has been little success indetermining the nature of interaction bet -ween rubber and bitumen. Different data isfound in literature about expansion ofrubber in bitumen. The reason for that couldbe the differences in solubility parametersof the components under the influence ofrising temperature.

When rubber particles are immersed in bitu -men, they absorb components of similarsolubility and quickly expand. Strong cross-links between elastomeric chains preventthe rubber particles to dissolve completelyin the liquid bitumen. With lengthening ofreaction time liquid penetrates inside theinner structure of the polymer and expan -sion continues. It has been determined thatthe expansion is linear during the first 90seconds after which it slows down. Rubberparticles can expand 3- to 5-fold the initialvolume. The expansion rate of rubberparticles in bitumen depends on tempe -rature and contact period, chemical com -position of bitumen (content of lighterfractions), type of rubber, and particle size.The chemical nature of bitumen dictates theexpansion rate balance, while the viscosityof bitumen dictates the speed of expansion.

In the preparation of rubberised bitumenonly rubber particles up to 0.8 mm in sizeare used, i.e. crumb rubber. Various pro por -tions of rubber particles are added to roadbitumen, ranging from 5 m% to 20 m%,depending on the nature of input bitumenand desired output properties of rubberisedbitumen. Rubber is added to hot bitumen(190 – 230 °C) and stirred up to 1 hour forthe rubber to expand. Rubberised bitumenis then stored at a temperature of 175 °C.Rubberised bitumen does not yet have goodstorage properties and is thereforeproduced in the same place as the asphaltmixture. It must be used up in 24 hours'time otherwise the polymers will begin tobreak down, the rate of which can bedetermined by viscosity measurements. Ifproperties of rubberised bitumen havechanged before use, fresh rubber particlesand fresh bitumen need to be added so as toobtain the desired properties.

Photo 3 (on page 29): A sample of rubbermodified bitumen

The technology for rubber modified bitu menproduction has been developed in the USA.Mixing plants differ slightly from one ano therin mixing methods and their capacities.

RMB products in the USA are standardisedand their properties must meet the require -ments laid out in the D 6114-97 (2002)standard which includes, in addition to RMBrequirements, requirements for input mate -rials, i.e. crumb rubber and input roadbitumen, and states examination proce -dures. The standard divides RMB into threetypes based on use in different climaticareas. Climatic conditions are determinedby minimum and maximum average monthlytemperatures. The climate is:

• hot if the average monthly temperaturesare between -1 °C and + 43 °C and use ofharder input bitumen is recommended.RMB Type I (PG 65-16) is used.


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• mixed if the average monthly tem pe -ratures are between -9 °C do + 43 °C anduse of somewhat softer input bitumen isrecommended. RMB Type II (PG 58-22) isused.

• cold if the average monthly temperaturesare between -9 °C do + 27 °C or lower anduse of soft input bitumen is recom -mended. GmB Type III (PG 52-28) is used.

Production of rubberised asphalt mixturesScrap tyre crumb rubber can be incor po -rated into asphalt mixtures using twodifferent methods, which are referred to asthe wet process and the dry process. In thedry process, rubber particles are used as aportion of the fine aggregate, while in thewet process rubber particles act as abitumen modifier, and the bitumen is usedin the production of hot asphalt mixtures.

Dry Process:The dry process is suitable for hot asphaltmixtures of the following types: AC bitu -minous concrete, SMA, and PA porousasphalts. It is not suited for production ofcold asphalt mixtures and surfacedressings. In the dry process crumb rubberis added in the place of fine aggregate (1 to3 % of the weight of aggregate in mixture).Crumb rubber is first mixed with aggregate,then bituminous binder and filler areadded.

The dry process was developed in Sweden itthe late 60's and was patented under thename of PlusRide.

The crumb rubber consisted of particlesbetween 4.2 and 2.0 mm in size. Targetporosity of mixture was 2 to 4 % and isusually attained with a bitumen content of7.5 to 9 %.

The dry process was improved in the early90's by including both coarse and finerubber particles, pre-treated with a sub -stance that increases particle expan sion.Lately crumb rubber is added in the pro -portion of up to 2 % of the weight of asphaltmixture of finer grade for AC surfbituminous concrete.

Particle size distribution of fractions needsto be designed in a way to leave enoughroom for the rubber particles. Unreactedrubber takes up the same amount of room asstone fraction. In bituminous concretetypes with a smaller nominal prticle sizedistribution, finer grades of rubber par -ticles need to be used. Crumb rubber has tobe as dry as possible and should not containmore than 0.75 % of moisture, which isessential in the wet process.

For the production of bituminous concrete,crumb rubber can be added by means of acellulose fibre dosage system, a system foraddition of granulated asphalt, or manually,

where bags containing the exact amount ofcrumb rubber are emptied into the mixer.The added amount of crumb rubber has tobe controlled and always constant as it hasa great effect on target properties of dryprocess rubberised asphalt mixtures.

In mixing, it is necessary to extend mixingtime and raise the temperature of stoneaggregate. First, crumb rubber and stoneaggregate need to be dry-mixed for theparticles to mix well before adding thebituminous binder. The temperature of theasphalt mixture should be between 149 0Cand 177 0C. The rubberised asphalt mixtureshould be conditioned in a silo for 1 hourbefore transporting it to the site.

Wet process:The production of hot asphalt mixturesusing the wet process is essentially the sameas the production of conventional asphaltmixtures. The asphalt plant needs to beequipped with the proper technology, i.e. itshould have a rubberised bitumen mixer,pumps strong enough to enable pumping ofa more viscous binder, and nozzles wideenough to allow expanded rubber particlesto pass through.

A lot of attention must therefore be paid toinput materials for preparation of polymermodified bitumen and to the mixing pro -cess. It has been found that not all bitu mensources are suitable for modification withrubber.

The following needs to be checked andverified:• source and type of bituminous binder• source and granulometry of crumb rubber• the required amount of crumb rubber to

be added to bitumen in order to attainthe desired properties

• appropriate reaction time• mixing temperature• intensity of mixing• need for additives

The wet process is suitable for all types ofhot asphalt mixtures, surface dressings, andstress absorbing membranes both as inter -layers or surface layers.

Casting of rubberised asphalt mixturesWith bituminous concrete, the same amountof rubberised asphalt mixture is required toattain the intended layer thickness as withconventional mixtures. With rubberisedSMA a slightly larger quantity of materialneeds to be used for the same intendedthickness than with conventional SMA.

When transporting rubberised asphalt mix -tures to the site it is recommended that truckload bins not be sprayed with petro leum oil,but with soap water or silicone-in-wateremul sion. I suppose that rapeseed oil wouldalso be suitable. Namely, petroleum oil reacts

with rubber particles, which can affect theproperties of rub berised asphalt mixture.

It is important not to cast rubberisedasphalt at temperatures lower than 10 °C;also, layer thickness should not exceed 3 cmas that can negatively affect its compaction.

The temperature of asphalt mixture justbefore casting should be between 120 °C and160 °C. Rolling should continue as long asthe temperature of the layer is above 60 °C(according to some sources above 100 °C) inorder to prevent expansion of compactedrubber particles.

Pneumatic rollers are not allowed as rubbersticks to the tyres of the roller. It isrecommended to use at least three 8-tonnerollers with smooth (metal) surfaces orheavier (in the USA rollers heavier than 15tonnes are used). Some dish detergent isadded to the water used for cooling downthe cylinders to prevent sticking to theasphalt mixture. Literature indicates staticrolling, although the Phoenix experts toldus that vibratory rolling can be used in part.

If the surface is sticky after rolling somesand is sprinkled over it.

Quality controlWith dry process mixing, granulometry ofinput crumb rubber, weight percent ofrubber particles in the rubberised asphaltmixture, pre-treatment of crumb rubberwith catalyst, and mixing time in asphaltmixer must be controlled. Because thebinder only partially reacts with the rubberduring dry mixing process, it is not possibleto determine binder properties directly.

Quality control of produced mixtures andcast layers is performed as with conven -tional asphalt mixtures.

Quality control systems in the USA are moreadvanced in the wet process of production,which is generally used, as the reactionbetween rubber particles and bitumen iseasier to control.

Crumb rubber is analysed for moisture (lessthan 0.75 %) and its specific weight isdetermined (1,15 ± 0,05). Grading curve isthen designed where the particles must notbe larger than 2.36 mm in size. The contentof steel particles must not exceed 0,01 m% andthe content of fibres must not exceed 0,5 %.

Input bitumen is tested for viscosity,penetration under two sets of differentconditions, softening point and resilience,flashpoint, and penetration after ageing.

Photo 4 (on page 30): Resilience testing ofrubberised bitumen

Rubber modified bitumen is subjected to

the following laboratory tests:• cone penetration• viscosity testing using rotary viscometer

(in the USA we were shown a handyviscometer for quick analysis)

• resilience (elasticity) testing performedsimilarly to penetration but with a bluntneedle-tip

• ring and ball softening point testing.

In the mixing plant viscosity tests areperformed every few hours using the quickanalysis viscometer, especially prior to thestart of asphalt mixture production.

A visit to Phoenix, ArizonaBetween 22 and 26 March 2010 delegatesfrom ZAS and CP Asfalt asphalt mixtureproducer were hosted by the RubberPavements Association (RPA).

RPA is a non-profit industry association,established in 1985, comprising of materialproducers, equipment manufacturers, con -trac tors who use crumb rubber in pave -ments, as well as institutes and clients.

We were received and guided by theexecutive director of the Association,Douglas D. Carlson, who prepared for us anAsphalt-Rubber Technology Tour.

We visited the Maricopa County Departmentof Transportation (DOT), where we met withJohn Shi and Scrap Tire Program Admi -nistrator Bill Thornton. The gentlemen madean introductory talk about the Arizona'swaste tyre programme, the objective ofwhich was to set up organised and contract-bound processing of scrap tyres for thewhole of Arizona, at the present timeundertaken by CRM (Crumb Rubber Manu -facturers). We learned some interes tinginformation, including the fact that theyprocess around 5 million scrap tyres peryear, which solved the huge environmentalproblem of illegal waste dumps.

Although reuse of tyres dates back to the1960's (McDonald), it became widespreadafter 1990; since 1999, wearing courses innew roads have mostly been made withrubberised asphalt.

Photo 5 (on page 30): Entrance to the Maricopa CountyDepartment of Transportation

We continued with a visit to ADOT, ArizonaDepartment of Transportation – MaterialsGroup, where we met with Ali Zareh, theirsenior pavement design engineer, and withhead of their laboratory (a state runlaboratory that performs quality control ofproduced and cast rubberised asphaltmixtures). Mr. Zareh gave an overview of thehistory of the use of rubber in pavements,from the SAMI system to the asphalt mostused now – OGAC, with 12.5 max. particle si -

ze, used in friction courses (ARFC), wherethe voids ratio in mixture is around 20 – 22 %v/v. He also presented different compo -sitions and the method of control of crumbrubber and bitumen mixing in production.We also took a tour of the laboratory forcontinual surveillance of prepared rub -berised bitumen.

We were also hosted by the Federal HighwayAdministration's Arizona Division, where wemet with Ken Davis, in charge of the nationalprogrammes.

Mr. Davis prepared for us a lecture on noisemeasurements and analyses, preceded by atalk on legitimacy of the introduction of tyrerecycling in Arizona and on a noticeable risein demand for the use of rubberisedproducts in paving in urban areas. Usingdifferent types of rubberised asphalt theyhave decreased the noise level by 3 to up to10 dB as compared to bituminous concretesurfaces. The Phoenix area is involved in apilot project whose report will include allfactors of different measurements (near avehicle, near a road), the climate, vehiclespeed etc.

In the following days we visited a leadinguser of rubberised asphalt, FNF Construc -tion, Inc., where we were greeted by thehighly experienced Mark Belshe. Hepresented an overview of the history ofrubberised asphalts and provided infor -mation on the wet (or McDonald) process,on the need for careful preparation, mixing(to maintain consistency), and casting ofrubberised asphalt mixtures in properambient conditions (above 10 °C).

We then took a tour of the CRM crumbrubber plant, the largest tyre processingplant in Arizona.

Photo 6 (on page 31): Primary shredding of scrap tyres

Motor vehicle tyres are first sorted, thenshredded into chips of about a few cm toapproximately 10 cm in size. These containmetal and textile fibres. The chips are thenprocessed using two different methods, theambient process and the cryogenic process.Finally, the obtained crumb rubber isseparated into different particle sizes bysifting and packed into big bags holdingabout 1 000 kg, then covered with black foilto protect them form UV radiation.

Photo 7(on page 31): Destocking of crumbrubber bags

We also visited the Arizona State University'sDepartment of Civil and EnvironmentalEngineering, where we were greeted byKamil E. Kaloush, Ph.D., P.E. and George B.Way, P.E., who has a 40 year experience ofworking with asphalt. The meeting at the

University was in the form of Q & A anddebate.

Photo 8 (on page 31): Dr. Kaloush (ASU),left, and D. Carlson (RPA), right

We were taken on a tour of the laboratories,which mostly test functional propertiessuch as fatigue and stiffness with 4PB (fourpoint bending test, for which two AustralianICP apparatuses are used); they also owntwo apparatuses for cyclic triaxial loadingtests. Laboratory specimens are preparedusing a gyrator for triaxial loading tests anda compactor which they have developed forstiffness testing.

We concluded our visit with a meeting withAndy Cox, manufacturer of mixing equipmentfor mixing rubber into bitumen, at an asphaltplant near Phoenix. We saw mixing ofrubberised bitumen to be used duringnight-time of the same day and were showna large capacity mobile mixing plantconsisting of an input bitumen tank,reaction chamber where crumb rubber isadded and mixed with bitumen, and tanksfor storage of rubberised bitumen.

Photo 9 (on page 31): Reaction chamber andstorage tank for rubberised bitumen

The visit was extremely well organised andenabled valuable insight into work andpractices connected with rubberised asphaltmixtures. This will benefit our future work asthe technology is being brought to Europeand perhaps to Slovenia as well.

Photo 10 (on page 31): Participants of the study tour

ConclusionThis article intended to present a tech -nology that is well established in the USAand Asian countries, but is still only at a trialstage in Europe, where we are currentlytesting both wet and dry processes ofproduction. Research reports have latelybeen coming in increasingly large numberform Portugal, Sweden, Italy, Germany, andHungary.

Without doubt, this is a forward-lookingand environmentally friendly technology,which however has specific requirements inall stages of its use. These requirementsneed to be met to ensure successfulproduction and casting of durable asphaltthat will meet the expectations based onliterature data and experience in the USA.

Bojana Lukač, MScHead of LaboratoryZAG, Slovenian National Building and CivilEngineering Institute Ljubljana


IN ENGLISH


NOVIČKE

Asfalt, ki opozarjaV Italiji naj bi voznike na poškodbe navozišču opozarjale kričeče barve naasfaltu.

Barva v asfaltu opozarja na poškodbena vozišču. (Foto: Autoblog)

Italijanska študenta Domenico Diegoin Cristina Corradini sta začela s pobu -do »Street Safe«, s pomočjo kate re bo -sta predstavila napreden način opozar -janja na poškodbe na vozišču, s čimernaj bi olajšala vožnjo voznikom, njiho -va vozila pa obvarovala pred more bit -ni mi poškodbami.

Njun izum temelji na živo rumeni barvi,ki jo bo vseboval asfalt in ki se bo poka -zala, ko bo na vozišču nastala luknja.Kako učinkovita je njuna zamisel, bo -mo videli, ko bosta preizkus izvedla vpraksi, prva testiranja pa bodo v Italijinaredili šele konec leta 2010.

Strokovnjaki zamisli niso naklonjeni,pred vsem zaradi barvanja vezivnega

sredstva. Inženirji verjamejo, da je bo -lje razmišljati o izboljšanju tehno lo -gije, s katero razpolagajo danes in danove in drage rešitve prinašajo učinekšele tedaj, ko se na vozišču pojavijo po -škodbe. (Vir: Zurnal24.si, 17.3.2010)

Asfaltirana pristajalna stezatik ob morju

Nikakršnega prostora za napako si pilotne more privoščiti na letališču JuanchoE. Yrausquin v Sabi na NizozemskihAntilih. Poleg težke konfiguracije tere -na preglavice povzročajo še močni mor -ski vetrovi in pršec iz morja. Če se pri -sta nek ne posreči, se vse skupaj lahkokonča v klifih. (vir: internet)

Nov tip vulkanaNemški znanstveniki so odkrili povsemnov tip vulkana, ki namesto lave vse -buje asfalt.Gre za okoli 450 do 800 m visok vulkan,

Asfalterske novičke

ki so ga našli pod morsko gladino v Me -hi škem zalivu, v katerem živi vrsta naj -različnejših živali in bakterij.Asfalt se lahko ustvari tudi kadar se ne -ka teri specifični mikroorganizmi hra ni -jo s surovo nafto pod vodo.Medtem ko so manjše količine asfaltado sedaj že večkrat našli pod morskogladino, to niti približno ni podobnovulkanski najdbi, za katero do sedaj ni -ti nismo vedeli, da obstaja.Gerhard Bohrmann iz Raziskovalnegacentra za raziskave oceanov v Bremnu(D) je pojasnil, da se asfalt na splošnošte je za preveč sovražno okolje, da binu di lo pogoje za razvoj življenja. Nav -kljub temu so strokovnjaki v pod mor -skem vulkanu našli celotni ekosistem,ki ne le da živi na asfaltu, ampak se znjim tudi prehranjuje.Na podlagi prvih raziskav znanstvenikimenijo, da lahko takšen tip vulkananaj demo v prav posebnih pogojih, kivklju čujejo globino morja več kot 3000metrov ter slane usedline in usedlinesurove nafte. (Posted by Ropret Tadej, vir: www.svarog.org)

Lansko leto nam je bolezen vzela naša člana

Mitjo Žorga in Aleksandro Boštjančič

Mitja Žorga je bil član UO ZAS v 1. mandatnem obdobju od 1996 – 2000. S svojim angažiranjem je veliko prispeval k uspešnemu zagonu na novo ustavljenega društva. Celotno profesionalno kariero je posvetil asfaltu,

ki mu je pomenil življenje. Slovenskemu asfalterstvu je tako doma kot v tujini pustil neizbrisljiv pečat. Mitja zahvaljujemo se ti za vse kar si dal slovenskemu asfalterstvu.

Aleksandra Boštjančič je aktivno sodelovala pri organizaciji številnih kolokvijev o asfaltih in bitumnih v Gozd Martuljku. Zadolžena za organizacijo dobave bitumnov, nas je vedno

znova navduševala s svojo zagnanostjo, umirjenostjo in profesionalnim pristopom. Za prispevek pri razvoju ZAS-a se Aleksandri najlepše zahvaljujemo.

Ohranili ju bomo v lepem spominu.

V spomin


Nekatere objave o ZAS-u

Vsi asfalterji vabljeni na tradicionalni piknik ZAS, ki bo 27. maja 2010 v Klečah

ZAS PIKNIK 2010

PROGRAM DELA

1. Splošne naloge

• koordiniranje asfalterske dejavnosti v Sloveniji• sodelovanje s sorodnimi organizacijami doma in v tujini• zagotavljanje sredstev za delovanje združenja• vodenje vseh organov združenja

2. Organiziranje strokovnih srečanj in izobraževanj

• strokovno srečanje (maj 2010)• redno letno srečanje predstavnikov odbora podjetij in družb (november 2010)• 3. dan asfalterjev (november 2010)• izobraževanje tehničnega asfalterskega kadra (marec 2011)• 15 let ZAS-a

3. Priprava in uveljavitev tehnične regulative

• prevodi standardov SIST 1038• prevzem s strani EAPA pripravljenih dokumentov

4. Priprava gradiv za

• izobraževanje,• bilten »Od skupščine do skupščine«

5. Priprava strokovne literature 2010-2011

• Priročnik za izvajanje asfalterskih del• Brošura: Asfalt 6

Program dela za leto 2010

Strokovna srečanja v letih 2010/2011

Professional Meetings in 2010/2011

•7 – 10 June 2010: TRA 2010 in Brussels;www.traconference.eu

•15 - 17 September 2010: Strassen- und Verkehrskongress der FGSV; www.fgsv.de

•21 – 23 October 2010: 10. Slovenski kongres o cestah in prometu; www.drc.si

•15 – 18 February 2010: World of Asphalt, Cincinnati, Ohio (USA)

•13 - 15 June 2012: 5th Eurasphalt & Eurobitume Congress,Istanbul, Turkey www.eecongress.org

•25 November 2010: 3. Dan Asfalterjev ZAS.


aktivnosti v preteklem letu (maj 2009 - maj 2010) 14 ... · 12. kolokvij o asfaltih in bitumnih ......

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