Ge04材料力学-拉伸与压缩

1、各点位移相同各点位移相同各点应变相同各点应变相同各点应力相同各点应力相同AFN= =s sNsFANss=AFAFNsAFN= =s s= 0AM030.75)(31=FNkN23111N.= NF= 0DM0sin30230.6)(3.2o21=NN.kN17422N.= NFAF2N=s2325143101744=.MPa151s= 0.63.2mkN2 .311N=FkN1 .742N=Fd2 = 25 mm42Nss=dF4NsFd mm81516014310231431.=dmm32416043110174432.=d= 0AM030.75)(31=FN480421211N1ss=d

2、FdF.)(FNF8011N.=0.8421sdFkN298804160251432.= 0.63.2m= 0AM480421211N1ss=dFdF.)(FNF8011N.=0.8421sdFkN298804160251432.=030.75)(31=FN 0.63.2m= 0DM0sin30230.6)(3.2o21=NN.122N3752NNF.=1.9422sdFkN298.F491422222N2ss=dFdF.)(kN81=FkN081914160351432.= 0.63.2mFNF8011N.=F91.= 0AmFLbN=)tan()cos(4=sinNbFLNF=sinNss

3、=AbFLAFssinbFLAAlgG=ssincosbFLbg=sincosC= 过小过小 过大过大F)(xff =0)(0=xxxf0)(0 =xxxf0)(0 =xxxf0)(0= =xxxfN11sinFFN=N22tanFFN=sint111N1ss=AFAF)(tanc222N2ss=AFAF)(ssint1FA =stanc2FA =由结点 B 的平衡可得12cosALLAV=sscossintantcLFLF=AC12LN11sinFFN=N22tanFFN=sint111N1ss=AFAF)(tanc222N2ss=AFAF)(ssint1FA =stanc2FA =由结点

4、B 的平衡可得12cosALLAV=sscossintantcLFLF= =cossin1tan1CV0dd=)(V0cossincossinsin122222=C2tan=4454o=sscossintantcLFLFV= 随着经济的发展，随着人类文明的进步，随着经济的发展，随着人类文明的进步，也随着环境的日益恶化和资源的日益减少，人也随着环境的日益恶化和资源的日益减少，人们对工程结构具有最优性质的要求越来越广泛们对工程结构具有最优性质的要求越来越广泛和迫切。和迫切。结构优化设计结构优化设计Structural Optimum DesignAF=s不受影响不受影响scosNAF=sinNAF

5、=AFN=scosAA =AFp =cosAF=scosp=2cos210)(s=sinp=2sin20)(s=s20cos=ssincos0=cosAF=scos0=602cos210)(ss=2sin20)(s=cos212s=bhFkN7 .105 . 011040202cos212=sbhF2sin2=bhFkN1 .11866. 0640202sin22=bhFkN10.7=Fxxu=xxxddd=xudd=xudd=xEudds=xEAFdN=A AAxxu=xxxddd=xudd=xudd=xEudds=xEAFdN=xEudds=xEAFdN=xEAFuxuxd00N=)()(

6、xE AxFLd0Nx)()(L = =D DE ALFLN= =D DA LLDD fLLf=D0=CBNABPkN36=CBABPN= 0BMNss=AF2Nmm514=sFA)(NlEAlFlDD=2Nmm633)(=lElFAD63332= tA514.=t0.8mDNF=P=6kN0.6m0.1mABxqF =N=LLNEAqLxEAxqxEAFL0202ddDEAqLL2=DqLF =NqLF =NEAqLL22=D1212lnhhhhEbFL)(=LxLhhhhhEbFLL012112ln=)(DxLhhhxh121=)(=xLhhhbbhxA121)(xEAFLLd0N=DxL

7、xhhhEbFLd0121=)(h2h1h2h1EAPaAB =EAPAEAaPAC222=EAPaACCS2221=EAPaABuA=AKBKvA= =EAPa122ABCSCS=P2)(A 点在变形后的真实位置A 点在变形后的近似位置RR=cos=124521142R)(2O=EAFauA =EAFavA)(1sec=RPN=cos2PNN=21cos2LE1A1E1A1E2A2PNN=21cos221N1coscos2=PNF32N2cos21=PNF1122AEAE=Dcos1111111N1AELNAElFl=2222222N2AELNAElFl=DDDcos21ll =FEA EALF2=LEAF2=FEALEAF2FEAFNNCA=FFFBCAB=NN EALF2=LEAF2=LEAF2FNNCA=FFFBCAB=NN FEAFEAFNNCA=FFFBCAB=NNEALFlABAB2N=DEALFlBCBC2N=DDD=BCABllLEAFFAB=2NLEAFFBC=2Ncos212=0