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BI TP MN VT LIU XY DNG

A- TNH CHT CBN CA VLXD

Bi 1- Mt vt trng thi m 10% c khi lng thtch 2,2kg/dm3, trng thi boho nc hon ton c khi lng thtch l 2,3kg/dm3. Bit vt c thtch khng i

khi m thay i v n=1g/cm3. Tnh khi lng ring ca vt.

Bi 2-Mt mu vi kh nng 300g, sau khi ht nc iu kin thng 3 ngy

m em cn c 309g. Bit hsbo ho nc l 0,7; khi lng thtch ca

kh l 2,4kg/dm3; ca nc l 1kg/dm3. Hy tnh mc ht nc theo khi lng v th

tch, rng v khi lng ring ca ny.

Bi 3- Mt vt khi bo ha nc hon ton c mc ht nc theo khi lng l 20%,

rng ca vt l 40%. Bit thtch ca vt khng thay i khi m thay i, khi

lng ring ca nc l 1g/cm3. Hy tnh khi lng thtch ca vt trng thi bo

ho.

Bi 4- Mt vt c khi lng ring l 2,6kg/dm3, rng 20%. Khi m tng 1% th

tng trung bnh vthtch ca vt l 0,2%. Hy tnh khi lng thtch ca vt

m 20%.

Bi 5- Mt vt c rng 20%, khi lng ring bng 1,3g/cm3. Khi m tng 1% th

tng trung bnh vthtch ca vt l 0,2%. Hy xc nh m ca vt bit rngm ny vt c khi lng thtch bng 1,2g/cm3.

Bi 6- Mt vt c khi lng ring l 2,2kg/dm3v rng bng 20%. trng thi bo

ho nc vt c khi lng thtch l 2kg/dm3. Cho bit ng biu din quan hgia

tng thtch tng i V v m c dng bc nht hsgc l 0,1. Tnh mc

ht nc theo khi lng ca vt.

Bi 7- Mt vt trng thi kh c khi lng 145,5g. Sau khi phbmt vt mt lp

paraphin vi khi lng 2,7g v em cn trong nc c khi lng l 48,2g.

trng thi bo ha nc hon ton vt c khi lng th tch l 1,75g/cm3. Hy xc

nh khi lng ring ca vt. Bit thtch ca vt khng thay i khi m thay i.

Cho p=0,9g/cm3, n=1g/cm

3. (Ch thnh lp cng thc trc khi p dng)

Bi 8- Mt vt trng thi kh c khi lng l 152g c bc mt lp parafin c khi

lng 4,5g sau em cn trong nc c 71,5g. Cng vt trng thi m th c

khi lng thtch l 2,1 g/cm3. Hy xc nh m tng ng vi khi lng thtch

? Bit rng khi m ca vt tng 1% th tng trung bnh v thtch ca vt l

0,13%.(p=0,9g/cm3;

n=1 g/cm3). (Ch thnh lp cng thc trc khi p dng)

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Bi 9- Mt mu vt trng thi kh c khi lng l 146g. Sau khi phbmt lp

parafin c khi lng 5,4g, em cn trong nc c khi lng l 67,4g. Nu cng

mu cho ht nc ti trng thi bo ho th c khi lng thtch l 2,2g/cm3. Hy

xc nh mc ht nc theo khi lng ca vt nu bit bit rng quan hgia

tng thtch tng i v m ca vt dng tuyn tnh vi hsgc l 0,15.

Cho p= 0,9g/cm3; n= 1g/cm

3. (Ch thnh lp cng thc trc khi p dng)

Bi 10- Mt vt c khi lng trng thi kh l 300g. Bc kn vt ny bng paraphin

v em cn trong nc c 99,2 g. Nu cng vt ny cho ht nc sau 3 ngy m

em cn c 375 g. Hy xc nh khi lng th tch ca vt trng thi bo ha.

Bit rng m ca vt v tng trung bnh vthtch c quan htuyn tnh vi h

sgc l 0,12. Cho khi lng paraphin bc xung quanh vt l 7,2 g, khi lng th

tch ca paraphin l 0,9 kg/dm3, khi lng ring ca nc l 1,0 kg/dm3. (Ch thnh

lp cng thc trc khi p dng)

Bi 11- Mt vt c khi lng kh l 220g. Bc kn vt ny bng paraphin v em cn

trong khng kh c 229g, cn trong nc c 89 g. Hy xc nh khi lng th

tch ca vt trng thi bo ha nc. Bit rng khi m ca vt tng 1% th

tng trung bnh v th tch ca vt l 0,15%. Cho khi lng th tch ca paraphin l

0,9 kg/dm3, khi lng ring ca nc l 1,0 kg/dm3, mc ht nc theo thtch ca

vt l 10%. (Ch thnh lp cng thc trc khi p dng)

Bi 12- Tnh khi lng ring, khi lng thtch kh ca mt vt. Bit rng trng

thi bo ho nc, vt ny cho vo nc th ni ln 2/7 th tch. Bit vt c th tchkhng thay i khi bo ha nc. Cho rng ca vt trng thi kh l 37,5%;

bo ha nc l 55%. (Ch thnh lp cng thc trc khi p dng)

Bi 13- Mt loi vi c khi lng thtch trng thi bo ho l 2,55g/cm3, hs

bo ha nc 50%. Cng loi vi , khi trng thi kh nghin ra c dm c

khi lng thtch xp l 1,62g/cm3, rng xp 35%. Bit thtch ca vi khng

thay i khi m thay i. Hy xc nh khi lng ring ca vi. (Ch thnh lp

cng thc trc khi p dng)

Bi 14- Mt loi dm (c sn xut t vi nghin nh) trng thi kh c

rng xp l 34%, khi lng thtch xp trng thi kh l 1,65 g/cm3. Cho bit vi

sn xut ra loi dm c thtch khng thay i khi m thay i. Hi khi vi

bo ha nc vi mc ht nc theo thtch l 10% th khi lng thtch ca

vi l bao nhiu? Cho n= 1,0 g/cm3. (Ch thnh lp cng thc trc khi p dng)

Bi 15- Mt loi vi c tng trung bnh vthtch l 0,15% khi m tng 1%.

Bit vi ny trng thi kh th sn xut ra dm c khi lng th tch xp l

1,6kg/dm3v rng xp 37%. Xc nh mc ht nc theo khi lng v mc ht

nc theo thtch ca loi vi trn nu bit trng thi bo ha vi ny c khi

lng thtch l 2,7kg/dm3. (Ch thnh lp cng thc trc khi p dng)

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B- B TNG

Bi1-a/Tnh liu lng vt liu thc tdng trong 1m3b tng M20. Bit b tng tic khi lng thtch l 2,32 T/m3v cp phi ca b tng phi hp theo tll:

X : NLT: Ck: k= 1 : 0,6 : 2 : 3,5.

Bit vt liu dng c cc tnh cht sau:

- Xi mng: ox = 1,3 kg/dm3; ax= 3,12 kg/dm

3.

- Ct: ock = 1,55 kg/dm3; ac= 2,6 kg/dm

3; Wc = 3,5%, Vc= 30%.

- : ok = 1,45 kg/dm3; a= 2,6 kg/dm

3; W=1,5%, V= 0%.

b/Tnh thtch b tng thu c tmt mtrn ca my trn c dung tch 500 lt.

c/Xc nh rng ca b tng bit hsthuho ca xi mng l 0,23dm3/kg xi mng

v githit b tng ti khng c lrng, nc tdo bay hi hon ton.

Bi 2-Mt loi b tng M20 c cp phi vt liu ti hin trng nhsau:

X:Ntr:C:= 1: 0,45: 2,5: 3,4

Bit vt liu sdng c cht lng tt, c cc chtiu nhsau:

- Xi mng PC30: ox= 1,30 g/cm3, ax= 3,12 g/cm

3

- Ct vng loi va: ock= 1,50 g/cm3; ac= 2,60 g/cm

3; Wc= 4,0%; Vc= 32%.

- dm c Dmax= 40mm:ok= 1,55 g/cm3; a= 2,56 g/cm

3; W= 1,5%; V= 0%.

- Nc sch: n= 1g/cm3

Sau khi trn, m b tng v th nghim xc nh c obti= 2,25 g/cm3.

a/Tnh lng vt liu cho 1m3b tng theo cp phi trn.

b/Tnh smtrn cn thit thi cng ht 300m3b tng theo cp phi trn. Bit my

trn c dung tch thng l 700(l).

c/Tnh rng ca b tng sau khi rn chc vi iu kin nc tdo trong b tng

bay hi hon ton. Cho bit hm lng nc lin kt ho hc ca khong vt xi mng

l 24% (so vi khi lng xi mng). Coi b tng ti khng c lrng.

Bi 3- Mt loi b tng c mc thit kl M25, lu ng yu cu SNyc= 4 cm, cpphi vt liu theo tnh ton nhsau: X : Ck:

k= 1 : 2,0 : 3,5

Bit vt liu c cc thng snhsau:

- Xi mng PC40: ox= 1,3 g/cm3.

- Ct vng loi va: ock= 1,50 g/cm3; ac= 2,56 g/cm

3; Wc= 4%; Vc= 32%.

- dm c Dmax=40mm: ok= 1,60 g/cm3; a= 2,65 g/cm

3;W= 1,5%; V= 0%.

- Nc sch: n= 1g/cm3

Cho bit lng nc l thuyt cho 1m3

b tng l 190 lt v hs thc nghim A l0,55. Hy tnh:

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a/Lng vt liu cho 1m3b tng theo cp phi trn v sbao xi mng (50 kg/1bao)

cn chun bvcng trng thi cng ht lng b tng l 600m3.

b/Tnh thtch b tng thu c tmt m trn trn c dung tch thng trn 600 lt.

Nu mun mi mtrn thu c 600 lt b tng th dung tch thng trn ti thiu l bao

nhiu lt?

Bi 4-Mt loi b tng M20 c cp phi l thuyt nhsau:

X : Ck: k=1: 2,4: 3,8

Bit vt liu dng c cht lng trung bnh, c cc thng snhsau :

- Ct : ac= 2,5 kg/dm3; oc

k= 1,50 kg/dm3; Wc= 5% ; Vc= 34%.

- dm: a= 2,4 kg/dm3; o

k= 1,45 kg/dm3; W= 1%; V= 0%.

- Xi mng PC30: ax= 3,13 kg/dm3; ox= 1,3 kg/dm

3.

Vt liu dng t yu cu vcht lng v thnh phn ht. Nc trn b tng sch,n=1g/cm

3; Hsthc nghim A=0,6; SNyc=6cm.

a/Tun theo nguyn tc th tch tuyt i, d tr lng vt liu cho 1 m3b tng v

lng b tng thu c tmt mtrn ca my trn c dung tch 500 lt theo cp phi

cho.

b/Tnh rng ca b tng sau khi rn chc vi iu kin nc tdo trong b tng

bay hi hon ton. Cho lng nc lin kt ha hc ca khong vt xi mng l 25%

(so vi lng xi mng). Coi b tng ti khng c lrng.

Bi 5-Mt loi b tng M20 c thnh phn danh ngha nhsau:

X : NLT : Ck : k= 1 : 0,62 : 2,5 : 3,7

Bit vt liu dng c cht lng tt, c cc chtiu sau:

- Ct: ock= 1,55 kg/dm3; ac = 2,65 kg/dm

3; Wc= 4% ; V = 32%.

- : ok= 1,45 kg/dm3; a= 2,60 kg/dm

3; W= 1,5% ; V = 0%.

- Xi mng PC30 : ox = 1,3 kg/dm3; ax = 3,12kg/dm

3;

- Nc sch: n = 1kg/dm3a/Tun theo nguyn tc thtch tuyt i dtr lng vt liu cho mt cng trng

sn xut 600m3b tng (xi mng tnh bng tn; nc, ct, tnh bng m3)?

b/Tnh thtch b tng thu c tmt mtrn ca my trn c dung tch Vo = 700(lt)

v smtrn cn thit thi cng ht lng b tng trn.

Bi 6-Mt loi b tng c thnh phn thc tnhsau:

X:Ntr:C: =1 : 0,36 : 2,08 : 3,56. Vt liu c sdng nhsau:

- Xi mng: ax = 3,15 kg/dm3; ox = 1,3 kg/dm

3

- Ct: ac= 2,6 kg/dm3; oc

k= 1,55 kg/dm3; Wc = 5%; Vc= 36%.

- : a= 2,5 kg/dm3; o

k= 1,45 kg/dm3; W= 0,5%; V= 0%.

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Bqua hm lng bt kh trong b tng ti, tun theo nguyn tc thtch tuyt i,

hy dtr lng vt liu chto 1m3b tng v lng b tng thu c tmt m

trn ca my trn c dung tch thng trn l 850 lt.

Bi 7-Mt loi b tng M20, cp phi vt liu ti hin trng nhsau:

X:NTR

:C

:

= 1: 0,40 : 2,13 : 3,76

Bit vt liu dng ti hin trng c cht lng tt v c cc thng snhsau:

- Xi mng PC30: ox= 1,3 g/cm3; ax= 3,12 g/cm

3.

- Ct vng loi va: ock= 1,55 g/cm3; ac= 2,56 g/cm

3; Wc= 5%; Vc= 34%.

- dm c: ok= 1,50 g/cm3; a= 2,65 g/cm

3; W= 1,5%; V= 0%.

- Nc sch: n= 1g/cm3

Dng nguyn tc th tch tuyt i d tr lng vt liu cn thit thi cng c

450m

3

b tng (xi mng tnh bng tn; nc, ct, tnh bng m3

) v smtrn cnthit thi cng ht lng b tng ni trn bit thng trn c dung tch 800 lt.

Bi 8-Tun theo nguyn tc thtch tuyt i, dtr lng vt liu cn thit v sm

sn xut 500 m3b tng M20 cho 1 cng trng ang thi cng. Bit lng nc l

thuyt cho 1m3b tng l 180lt v vt liu dng c cc thng snhsau:

- Ct : ock= 1,5 kg/dm3; ac = 2,6 kg/dm

3; Wc= 4% ; V = 30%.

- : ok= 1,46 kg/dm3; a = 2,5 kg/dm

3; W= 1% ; V = 0%.

- Xi mng PC30: ox= 1,3 kg/dm3; ax= 3,13 kg/dm

3

Vt liu dng t yu cu v cht lng v thnh phn ht. Nc sn xut b tng

sch. Cho hstng lng va kdl 1,4; Hsthc nghim A = 0,55, lu ng

ca hn hp b tng yu cu l SN = 6cm v dung tch thng trn l Vo = 750lt.

Bi 9-Mt cng trng ang thi cng 850 m3b tng M25 c lu ng yu cu

SNyc= 4 cm v hstng lng va khi thit kcp phi l kd= 1,4. Bit vt liu ti

hin trng c cc thng snhsau:

- Xi mng PCB40: ox= 1,3 g/cm3; ax= 3,12 g/cm

3.

- Ct vng loi va: ock

= 1,56 g/cm3

; ac= 2,65 g/cm3

; Wc= 3,5%; Vc= 31%.- dm c: o

k= 1,47 g/cm3; a= 2,56 g/cm3; W= 1,5%; V= 0%.

- Nc sch: n= 1g/cm3

Cho bit lng nc l thuyt cho 1m3b tng l 180 lt v hs thc nghim A l

0,60. Hy tnh lng vt liu trng thi m tnhin cho 1m3b tng ni trn v s

ngy cn thit thi cng ht sb tng , bit mt ngy cng trng c ththi cng

c 20 thng trn, dung tch ca thng trn l 850 lt.