pm interaction diagram (concrete) - structural engineering other technical topics - eng-tips
DESCRIPTION
PM Interaction Diagram (ConcreteTRANSCRIPT
-
4/9/2015 PMinteractiondiagram(concrete)StructuralengineeringothertechnicaltopicsEngTips
http://www.engtips.com/viewthread.cfm?qid=211905 1/2
Home>Forums>StructuralEngineers>Activities>StructuralengineeringothertechnicaltopicsForum
PMinteractiondiagram(concrete) thread507211905
Share
Whencheckingaflexureandaxialmember,howtofindoutthesafetyofthemember?
OftendrawingPMinteractiondiagram?Orsimplycheckingtheequationofthesafety?
WhenyoudrawthePMinteractiondiagram,usingthesoftwareorspreadsheet?
Andtellmethesoftware'sname(commercialorfree)
IuseanexcelspreadsheetthatcalculatesthemaxPvaluewithoutM,thebalancedconditionforPandMandthemaximumMvalue.Allofthisisforagivenbararrangement.
IcalculatethemaxPvalueallowedandthendrawaseriesoflinesthroughthese4points.Thisismyinteractiondiagram.Ithencheckloadingconditionsagainstthisinteractiondiagramandhopefullyallpointsfallwithin.
Ifnot,thenIchangethebararrangement.Thespreadsheetthencalculatesmaximumstirrupspacingandmystandarddetailstakecareofthetiearrangementandspacingatthetopandbottom.Ifshearisanissue,IdoitbyhandIhaven'thadachancetomodifythespreadsheettodothis.
youmindgivingmethisspreadsheet
Ifyoudon'thaveaccesstoaprogramlikePCACOL,Iwouldjustconstructaninteractiondiagrambyhand.It'sreallyprettysimpletodo.Iusethefollowingpointsonthediagram:PureAxialLoad,Decompression(whereonefacehas0strain),BalancedPoint(compressioncontrolledpoint),TensionControlledPoint,andPureMoment.Itisimportanttonotethatthephifactorwillbethesameformomentandaxialdependingonthestraininthesteel.
Plottingthesethreepointswillcertainlywork,butkeepinmindthatit'sfairlyconservative.
StructuralEIT,Ibelievethisiswhatyoumeant,butitwasn'tcleartome:atanygivenP,Mpointonthecurve,thereisonlyonephifactorwhichwillbeappliedtobothaxialandflexuralcapacity,andwhichdependsentirelyonthestrainintheextremelayerofsteel(thisiscorrect)
http://www.cement.org/buildings/TimesavingColumnsIA.pdf
Also:
http://www.ceref.com/short_col.htm
http://www.strunet.com/concrete_column/ccol03.html
yadik,sendthatspreadsheetmyway!
FloridaDepartmentofTransportationhasareallygoodbiaxialcolumnanalysisprogram.Youcanbuildarbitraryshapes,rectangular,squareetcquicklyandeasily.ThanenteryourloadcasepointsandaMathCadspreadsheet
3
-
4/9/2015 PMinteractiondiagram(concrete)StructuralengineeringothertechnicaltopicsEngTips
http://www.engtips.com/viewthread.cfm?qid=211905 2/2
willproducea3Dbiaxialcolumn.YoucanviewtheorbitsorthePMdiagrams.Reallyeasytouse.Theonlydrawbackisthatyoumustbeusingashortcolumn.Momentamplificationisnotdoneforyou.
http://www.dot.state.fl.us/Structures/proglib.htm
dikCanIgetacopyofthespreadsheetyouusefordevelopingthepointsontheMPdiagram?
PrecisionBellowsExpertDesignAssistanceAdvancedManufacturing&Assembly
Join|IndeedJobs|Advertise
Copyright19982015ENGINEERING.com,Inc.Allrightsreserved.Unauthorizedreproductionorlinkingforbiddenwithoutexpressedwrittenpermission.