STAAD.Pro V8i Technical Reference Manual - Bentley

1 (SELECT series4)TechnicalReferenceManualDAA03778 0-1/0005 Lastupdated:19 November2012 CopyrightInformationTrademarkNoticeBentl ey,the"B"Bentleylogo, , , 2012,BentleySystems, ,fileformats,andaudiovisualdisplays;mayo nlybeusedpursuanttoapplicablesoftwarelic enseagreement;containsconfidentialandpro prietaryinformationofBentleySystems, ,Vista,SQLS erver,MSDE,.NET, ,theAdobelogo,Acrobat, ,itsagenciesand/orinstrumentalities(" "), "commercialcomputersoftware"and"commerci alcomputersoftwaredocumentation,"respect ively, ,and"restrictedcomputersoftware" (a), ,modification,reproduction,release,perfo rmance, , , , , ,Incorporated,685 StocktonDrive,Exton, iTableofContentsToviewtheEndUserLicenseA greementforthisproduct, , ,Concrete, ,shearwalls, ,B759C759D759E760F760vi ,K760L760M760N761O761P,Q761R761S761T762U ,V,W,X,Y,Z762 TechnicalSupport763 TechnicalReferenceManual ,concrete,andtimberdesignisavailableinSe ctions2,3,and4ofthismanual, ,Hints,andWarningsItemsofspecialnotearei ndicatedasfollows: ,filepaths,andfileextensions( ,C:/SPROV8I/ ) >characterstodistinguishmenulevels.

2 ( ,File> ).UserInputAbold,fixedwidthtypefaceisuse dtoindicateinformationwhichmustbemanuall yentered.( ,TypeDEADLOAD asthetitleforLoadCase1).STAADPageControl sA"|"characterisusedtorepresentthepageco ntrollevelsbetweenpagesandsub-pages.( ,SelecttheDesign|Steelpage).Terminologyl Click-Thisreferstotheactionofpressingamo usebuttonto"click" , (SELECT series4)DocumentConventionslSelect-Indic atesthatthecommandmustbeexecutedfromamen uordialog(synonymouswithClick).Usedwhenr eferringtoanactioninamenu,drop-downlist, listbox, (typically) "cursors" , (,) , 'sModulusistakenas29,000, , ,ormiddle,dot( ).Forexample,P=F ( ) [ ] ( ,braces){ }Forexample,Fa=[1-(Kl/r)2/(2 Cc2)]Fy/{5/3+[3(Kl/r)/(8 Cc)]-[(Kl/r)3/(8 Cc3)]}DocumentConventionsTechnicalRefere nceManual 34 (SELECT series4) , ,Concrete, (GUI)isnormallyusedtocreateallinputspeci ficationsandalloutputreportsanddisplays( SeetheGraphicalEnvironmentmanual).Theses tructuralmodelingandanalysisinputspecifi cationsarestoredinSTAAD inputfile atextfilewithextension.

3 , engine toproduceresultsthatarestoredinseveralfi les(withfileextensionssuchasANL,BMD,TMH, etc.).TheSTAAD analysistextfile( ) (displacements,member/elementforces,mode shapes,sectionforces/moments/displacemen ts,etc.)thatareusedbytheGUIinthepostproc essingmode. ,concrete,andtimberdesignisavailableinSe ctions2,3,and4ofthismanual, (SELECT series4) , (oryou,theuser)communicateswiththeSTAAD analysisenginethroughtheSTAAD inputfile( ). TheSTAAD inputfilecanbecreatedthroughatexteditoro rtheGraphicalUserInterface(GUI) , , :Someoftheautomaticgenerationfacilitieso ftheSTAAD ,theformulationofinputistheresponsibilit yofyou, , (globalXorZ)movementofthestructure[FX,FZ ,andMYarerestrainedateveryjoint].Thefloo rframing(inglobalX-Zplane) , :DegreesoffreedomineachtypeofStructure8 (SELECT series4) ,SI2, , (orrotations) ,inJOINTDISPLACEMENT output, , ,columns,slabs, , , (incidences) , (orelement) ,Kilogram, "Syst meinternationald'unit s",whichusesmetres,kilograms, ,Pound, (X,Y,Z) ,u2,u3andtherotationaldegreesoffreedomar edenotedbyu4,u5& :Cartesian(Rectangular)CoordinateSystemC ylindricalCoordinateSystemInthiscoordina tesystem,theXandYcoordinatesoftheconvent ionalCartesiansystemarereplacedbyR(radiu s)and (angleindegrees).

4 :CylindricalCoordinateSystem10 (SELECT series4) 'i'andendjoint'j'.Thepositivedirectionof thelocalx-axisisdeterminedbyjoining'i'to 'j' , (s) :WhenGlobal-YisVerticalFigure1-6:WhenGlo bal-ZisVertical(thatis,SET Z UPisspecified)12 (SELECT series4) (Longlegsback-to-back)Angle-SD(Shortlegs back-to-back)WideFlange-TChannel-STChann el-DPrismaticTube-STTable1-1:Localaxissy stemforvariouscrosssec-tionswhenglobalYa xisisverticalFigure1-7:Localaxissystemfo rasingleangleasdefinedinstandardpublicat ions,whichdiffersfromthelocalaxisofSTAAD A ngle-STorAngle-RA 13 WideFlange-STWideFlange-TBWideFlange-CMA ngle-LDAngle-SDChannel-STWideFlange-TCha nnel-DPrismaticTube-STAngle-STAngle-RATa ble1-2:Localaxissystemforvariouscrosssec -tionswhenglobalZaxisisvertical(SETZUP isspecified).Note:Thelocalx-axisoftheabo vesectionsisgoingintothepaper14 (SELECT series4) , ( ) , ,asinthecaseofacolumninastructure,thebet aangleistheanglethroughwhichthelocalz-ax is(orlocalYforSETZUP)hasbeenrotatedabout thelocalx-axisfromapositionofbeingparall elandinthesamepositivedirectionoftheglob alZ-axis(globalYaxisforSETZUP).

5 Whenthelocalx-axisisnotparalleltotheglob alVerticalaxis,thebetaangleistheanglethr oughwhichthelocalcoordinatesystemhasbeen rotatedaboutthelocalx-axisfromapositiono fhavingthelocalz-axis(orlocalYforSETZUP) paralleltotheglobalX-Zplane(orglobalX-Yp laneforSETZUP)andthelocaly-axis(orlocalz forSETZUP) , (orajointnumber)whichwillbeareferencepoi ntlocatedinthememberx-yplane(x-zplanefor SETZUP) ,theprogramautomaticallycalculatestheori entationofthememberx-yplane(x-zplaneforS ETZUP).Figure1-8 ,theX,Y, ,theX,Y, :Betarotationofequal&unequallegged'ST'an gles16 (SELECT series4) :TheorderofthejointnumbersintheMEMBERINC IDENCES commanddeterminesthedirectionofthemember ' :Betarotationofequal&unequallegged'RA' 17 Figure1-11:MemberorientationforvariousBe taangleswhenGlobal-Yaxisisvertical18 (SELECT series4) :MemberorientationforvariousBetaangleswh enGlobal-Zaxisisvertical(thatis,SETZUP isspecified) 19 Figure1-13:MemberorientationforvariousBe taangleswhenGlobal-Yaxisisvertical 20 (SELECT series4) , (triangular)or4-noded(quadrilateral).

6 Ifallthefournodesofaquadrilateralelement donotlieononeplane, "Surfacestructures"suchaswalls,slabs, , "PlateElementMeshGeneration" 21 YoumayalsousetheelementforPLANESTRESS actiononly( ,membrane/in-planestiffnessonly). ,centernode"O"(seethefollowingfigure) :Fictitiouscenternode(inthecaseoftriangu larelements,afourthnode;inthecaseofrecta ngularelements,afifthnode) ,itisessentialthatthenodesbespecifiedeit herclockwiseorcounterclockwise(seethefol lowingfigure).Forbetterefficiency, :1,andpreferablylessthan4 (SELECT series4) : , 23 Theincompletequadraticassumedstressdistr ibution: x yx xyx y yxyyx xy y xaaaa=10 0 0 0200 0 0 100 20 0 0 0 1 2 ..xyxy222212310a1througha10=constantsofs tresspolynomialsThefollowingquadraticstr essdistributionisassumedforplatebendinga ction:Figure1-18:Quadraticstressdistribu tionassumedforbendingTheincompletequadra ticassumedstressdistribution: MMMQQx yx xyx yxy yx y xyxyx yxyy x yaaaaa=10 0 0 0 0 00 00 0 0 10 0 0 0 00 0 0 0 0 0 1 0 0 0 1 0 0 0 0 0 0 10 0 0 0 0 0 1 0 1 0 (SELECT series4) (seethefollowingfigure) , ,withcornernodesonly, , , , :thecross-productofvectorsIJandJKdefines avectorparalleltothelocalz-axis, ,z= :thecross-productofvectorsIJandJLdefines avectorparalleltothelocalz-axis, ,z= , ,y= (average)ofthefourjointlocations(threejo intlocationsforatriangle).

7 Figure1-20:ElementoriginOutputofPlateEle mentStressesandMoments Forthesignconventionofoutputstressandmom ents, (SELECT series4) ,SQYS hearstresses(Force/unitlength/thickness) SX,SYMembranestresses(Force/unitlength/t hickness)SXYI nplaneShearStress(Force/unitlength/thick ness)MX,MY,MXYM omentsperunitwidth(ForcexLength/length)( ForMx, , ,whileMxycausestheelementtotwistout-of-p lane.)SMAX,SMINP rincipalstressesintheplaneoftheelement(F orce/unitarea). (Force/unitarea)VONT,VONB3 DVonMisesstressatthetopandbottomsurfaces ,where:VM= [(SMAX-SMIN)2+ SMAX2+ SMIN2]1/2 TRESCAT,TRESCABT rescastress,whereTRESCA=MAX[ |(Smax-Smin)|,|(Smax)|,|(Smin)|]Table1-3 , 27mustprovidethelocation(localX,localY) (SMAX&SMIN),themaximum2 Dshearstress(TMAX),the2 Dorientationoftheprincipalplane(ANGLE),t he3 DVonMisesstress(VONT&VONB),andthe3 DTrescastress(TRESCAT&TRESCAB) ,theTMAXandANGLE arebasedonlyonthe2 Dinplanestresses(SMAX&SMIN) SignConventionofPlateElementStressesandM omentsSee"PrintSpecifications" :Signconventionsforplatestressesandmomen tsFigure1-22:Signconventionforplatebendi ng28 (SELECT series4) :StresscausedbyMxFigure1-24 29 Figure1-25:TorsionFigure1-26:Membranestr essSxandSy30 (SELECT series4) :In-planeshearstressesSxyandSyxFigure1-2 8 31 Members,plateelements, , ,constants,releases,loads, , , ,tosavesomecomputingtime.

8 Examplesofefficientandinefficientelement numbering32 (SELECT series4) , , :eight-noded,isoparametricsolidelementBy collapsingvariousnodestogether, ,2, ,thegeometryoftheelementisexpressedbyint erpolatingfunctionsusingnaturalcoordinat esystem,(r,s,t) :Xh x= ii i=18,yh y= iii=18,zh z= ii i=18wherex,yandzarethecoordinatesofanypo intintheelementandxi,yi,zi,i=1,.., ,hiaredefinedinthenaturalcoordinatesyste m,(r,s,t).Eachofr,sandtvariesbetween-1an d+ ,i, ,thefunctionsaregivenbelow:uh u= ii i=18,vh v= ii i=18,wh w= ii i=18whereu,vandwaredisplacementsatanypoi ntintheelementandui,vi,wi,i=1, "bubble" 34 (SELECT series4) :LocalcoordinatesystemforasolidelementPr opertiesandConstantsUnlikemembersandshel l(plate)elements, ,theconstantssuchasmodulusofelasticityan dPoisson , :lNormalStresses:SXX,SYYandSZZlShearStre sses:SXY,SYZandSZXlPrincipalstresses:S1, S2andS3lVonMisesstresses:SIGE= [(S1-S2)2+ (S2-S3)2+ (S3-S1)2]1/2 Directioncosines:sixdirectioncosinesarep rinted,followingtheexpressionDC, , , , ,10,23,27,etc.

9 (RefertotheExamplesmanual) , "Surface"entities, , , ,andthesectionsofthismanualwheretheinfor mationmaybeobtained, , (SELECT series4) ,Y,andZrepresentthelocalandGX,GY,andGZth eglobalaxisvectors, ,wherethethumbindicatesthepositiveZdirec tion, (X=GYxZ).IfGYandZareparallel, ,YisavectorproductofZandX(Y=ZxX). :Localaxis& :forarectangularcrosssection, (Roark) (Cowper) (12EI/L3)/(1+ )Where: =(12EI)/(GAsL2)As= ( ) ,theshearstresseffectiveareaisusuallytak enastwo-thirds( ) (ShearForce)/(Shearstresseffectivearea) (ShearForce)/(Shearstiffnesseffectiveare a) (VQ)/(It)Insomecodesandforsomecrosssecti ons, :whenAYandAZarenotprovided,whenAYandAZar esettozero,whenAYandAZaresettoverylargen umbers,whenpropertiesarespecifiedusingPR ISMATIC,whenpropertiesarespecifiedthroug hausertable,whenpropertiesarespecifiedth roughfromthebuilt-in-table, :38 (SELECT series4) ,theusermaychoosetospecifythefollowingpr operties:lAY= ,YD,ZD,YB& ,whichareshowninthenextfigureare:lYD=Tot aldepthofsection(topfiberofflangetobotto mfiberofweb)lZD=WidthofflangelYB=Depthof stemlZB=WidthofstemForTrapezoidalbeams,Y D,ZD& ,whichtooareshowninthenextfigureare.

10 LYD=TotaldepthofsectionlZD=Widthofsectio nattopfiberlZB=Widthofsectionatbottomfib erTop&bottomaredefinedaspositivesideofth elocalZaxis, (inadditiontodeflectionduetoordinarybend ingtheory).Toignorethesheardeflection, Thedepthsinthetwomajordirections(YDandZD ) ( ) 39 Figure1-34:Prismaticpropertynomenclature foraTandTrapezoidalsectionTodefineaconcr etemember,youmustnotprovideAX,butinstead , , ,bystructuraltype, , , ,IZ,orIYFLOOR structureIX,IZorIYSPACE structureAX,IX,IY,IZTable1-4 , (SELECT series4) :CastellatedbeamelevationSincetheshearar easofthesectionsarebuiltintothetables, , "UserSteelTableSpecification"onpage326an dSee"PropertySpecificationfromUserProvid edTable" , "TaperedMemberSpecification" , ,COLUMN,CHANNEL, 41 WhenthekeywordBEAM isspecified,theprogramwillassignanI-shap edbeamsection(WideFlangeforAISC,UBsectio nforBritish).ForthekeywordCOLUMN also,theprogramwillassignanI-shapedbeams ection(WideFlangeforAISC,UCsectionforBri tish).