混凝土非线性分析-应力应变曲线输出

1、各位同学，这里几乎已经是最完整的命令流了，关于这方面工作，初步建议如下：（1）初步的模拟最好先不要考虑混凝土下降段，不要考虑混凝土的压碎，同时单元尺寸不要过小，以免影响收敛。（2）反复试算结果表明，混凝土的MISO和KINH模型、DP和MISES准则、剪力传递系数对模拟结果影响均不大，但在一定程度上影响了收敛性的好坏。（3）当解决了收敛问题之后，最大的难点是下降段，对于一个桥墩（柱）的反复荷载试验，引起承载力下降的原因大体可归结为：塑性铰区混凝土压碎脱落、纵筋屈曲，对于以剪切破坏为主的试件，还包括剪切滑移的影响。对于以黏结破坏为主的试件，还包括纵筋混凝土黏结滑移破坏。因此，能否正确模拟这些将是

2、模型正确与否的关键。众所周知，以link8单元模拟钢筋自然无法模拟纵筋屈曲，这样就把一个因素忽略了。（4）作者们最后采用了扩大的破坏面，坦率的讲，这也是为了模拟混凝土的压碎破坏而采取的没有办法的办法，鉴于作者水平有限，至今也无法对此做出更为合理的解释。破坏面到底扩大多少，仍无规律可循。且一旦打开压碎开关，会出现诸如难以收敛、“假压碎”等一系列问题。所以我们建议大家起初还是先不要考虑压碎为好。定义应力应变曲线1， 定义变量： 拾取主菜单：Main Menu>Time Hist postproc>Define Variables>在随之弹出的对话框中点击Add键，定义第一个变量序

3、号为2，选取第一个变量stress,确定与之对应的下一级选项（如Y-direction SY等）；返回定义变量对话框，再点击add键，定义第二个变量序号为3，选取第二个变量strain-elastic及以及对赢得下一级选项（如Y-dirn EPEL Y等，在应力-应变图中，其向量的取向应相同）。同理再定义变量4，选取变量strain-plastic及与之对应的下一级选项如Y-dirn EPEL Y等），在应力-应变图中，应变是弹性应变和塑性应变累加的总应变。为使其实现相加，还需进行以下操作：拾取主菜单：Main Menu>Time Hist postproc>math operat

4、ion>add,定义计算变量序号为5，同时在相应交互框内输入3和4。点击确认键，则由变量3，4代表的应变之和就存在变量5中。 2，绘制应力-应变曲线： 拾取主菜单：Main Menu>Time Hist postproc>setting>graph.设置x轴向变量为单变量，并将其变量序号定义为5。点击确定键退出退化框。拾取应用菜单：Utility Menu>plot ctrls>styles>Graphs>Modify axis.将x,y坐标轴分别命名为Y-strains,Y-stress,拾取主菜单：Main Menu>Time Hist

5、 postproc>graph variables. 在对话框上the first variable对应的交互框中输入2。点击确定键，则预想的应力-应变曲线就显示在屏幕上。 ok!试试看！欢迎大家继续批评指正！/prep7 et,1,solid65 et,2,link8 et,3,solid45r,1r,2,236e-6r,3,75.4e-6 r,4,151.2e-6 !混凝土本构关系mp,ex,1,2.522e10mp,prxy,1,0.2 mp,dens,1,2500tb,concr,1,1 tbdata,0.5,0.95,5e6,-1tb,miso,1,1,7tbtemp,0 tb

6、pt,0.00068,17.15e6tbpt,0.00136,28.03e6tbpt,0.00204,33.62e6tbpt,0.00272,35.96e6tbpt,0.0034,36.53e6tbpt,0.00408,36.53e6!纵筋的本构关系mp,ex,2,2.0e11mp,prxy,2,0.28 tb,bkin,2 tbtemp,0 tbdata,362e6,2e9！箍筋的本构关系mp,EX,3,2.1E11mp,PRXY,3,.27tb,bkin,3tbtemp,0tbdata,272.5e6,2.1e9 !建立模型local,11,1,0,0,0,0,-90,0 ！建立局部坐标系

7、，采用柱坐标，绕y轴顺时针转90度csys,11*do,j,1,8n,j,0.185,j*360/8,-0.6*enddo ngen,3,100,1,8,1,0,0,0.3 ！复制节点，3次，编号增量，源节点18，0,0,0.3ngen,4,100,201,208,1,0,0,0.15ngen,7,100,501,508,1,0,0,0.3type,2 ！指定单元属性，建立基础箍筋单元real,3mat,3*do,i,1,6*do,j,1,7e,(i-1)*100+j,(i-1)*100+j+1*enddoe,(i-1)*100+1,(i-1)*100+8*enddotype,2 ！建立柱上箍

8、筋单元real,4mat,3*do,i,1,5*do,j,1,7e,(i+5)*100+j,(i+5)*100+j+1*enddoe,(i+5)*100+1,(i+5)*100+8*enddotype,2 ！建立纵向钢筋real,2mat,2*do,i,1,11*do,j,1,8e,(i-1)*100+j,i*100+j*enddo*enddoallsel,all ！合并节点，压缩节点nummrg,allnumcmp,allwpcsys,1,11cylind,0,0.185,-0.6,0,0,360 ！建立圆柱，内外径i-or，高度z1-z2，起终角度cylind,0,0.185,0,0.45

9、,0,360cylind,0.185,0.3,-0.6,0,0,360cylind,0,0.185,0.45,2.25,0,360cylind,0,0.185,2.25,2.55,0,360cylind,0.185,0.20,2.25,2.55,0,360cylind,0,0.185,2.55,2.565,0,360wprota,90 ！绕y轴逆时针转90度vsel,s,1,7,1 ！选择体，选择类型，item，comb，最小编号，最大编号，增量vsbw,all ！体相减numcmp,all wprota,90 ！绕z轴逆时针转90度vsel,s,1,14,1 vsbw,all numcmp,

10、all vsel,s,1,28,1 vglue,all numcmp,all wprota,-90 wprota,-90 allsel,allvsel,s,1,16,1vsel,a,21,24,1vatt,1,1,1 vsel,s,17,20,1vsel,a,25,28,1vatt,2,1,3 allsel,all lsel,s,1,8,1 ！选择线lsel,a,11,22,1 ！补选（a）线lsel,a,25,40,1 lsel,a,43,46,1 lesize,all,2 ！线尺寸为2lsel,s,47,50,1 lsel,a,53,56,1lsel,a,58,73,1lesize,all

11、,2lsel,s,98,107,1 lsel,a,110,112,2lesize,all,1lsel,s,23,24,1 lsel,a,9,10,1lesize,all,2lsel,s,78,82,1 lesize,all,3lsel,s,83,87,1 lesize,all,6lsel,s,41,42,1 lsel,a,88,92,1lesize,all,2lsel,s,93,97,1 lesize,all,1mshkey,1 mshape,0,3d vsel,s,1,28vmesh,all allsel,all nummrg,allnumcmp,allwprota,90 csys,0all

12、sel,all /solu ！进入加载、求解csys,11nsel,s,loc,x,0.3 ！选择半径在x=3处的节点，并施加约束d,all,allallsel,all OUTRES,ALL,2 ！输出获得的解csys,0pred,on ！打开预应力选项cnvtol,f,0.05,2 !定义收敛条件,使用缺省的VALUE autots,1 !打开自动时间步控制 lnsrch,1 !打开线性搜索 ncnv,2 !如果不收敛时结束而不退出 neqit,50 !每一子步中方程的迭代次数限值 savetime,1 ！定义第1载荷步nsubst,10asel,s,29,32,1sfa,all,pres,

13、5468699 ！在已选择的面上施加压力荷载allsel,allacel,9.8 ！重力加速度y=9.8kbc,1 ！阶跃加载方式lswrite,1 time,10 ！定义第2荷载步cp,1,ux,298,300,303 !将节点298,300,303ux向位移耦合d,298,ux,0.015 ！再借点298处施加ux位移0.015allsel,all KBC,0allsel,all NSUBST,20,1000000,10 lswrite,2time,20 ！定义第3载荷步d,298,ux,-0.015allsel,all KBC,0allsel,all NSUBST,100,1000000

14、,10 lswrite,3time,30 ！定义第4载荷步d,298,ux,0.015allsel,all KBC,0allsel,all NSUBST,100,1000000,10 lswrite,4time,40 ！定义第5载荷步d,298,ux,-0.015 allsel,all KBC,0allsel,all NSUBST,100,1000000,10 lswrite,5time,50 ！定义第6载荷步d,298,ux,0.015allsel,all KBC,0allsel,all NSUBST,100,1000000,10 lswrite,6time,60 ！定义第7载荷步d,298

15、,ux,-0.015allsel,all KBC,0allsel,all NSUBST,100,1000000,10 lswrite,7time,70 ！定义第8载荷步d,298,ux,0.015allsel,all KBC,0allsel,all NSUBST,100,1000000,10 lswrite,8time,80 d,298,ux,-0.015allsel,all KBC,0allsel,all NSUBST,100,1000000,10 lswrite,9time,90d,298,ux,0.015allsel,all KBC,0allsel,all NSUBST,100,1000

16、000,10 lswrite,10time,100d,298,ux,-0.015allsel,all KBC,0allsel,all NSUBST,100,1000000,10 lswrite,11time,110d,298,ux,0.03allsel,all KBC,0allsel,all NSUBST,200,1000000,10 lswrite,12time,120d,298,ux,-0.03allsel,all KBC,0allsel,all NSUBST,200,1000000,10 lswrite,13time,130d,298,ux,0.03allsel,all KBC,0all

17、sel,all NSUBST,200,1000000,10 lswrite,14time,140d,298,ux,-0.03allsel,all KBC,0allsel,all NSUBST,200,1000000,10 lswrite,15time,150d,298,ux,0.03allsel,all KBC,0allsel,all NSUBST,200,1000000,10 lswrite,16time,160d,298,ux,-0.03allsel,all KBC,0allsel,all NSUBST,200,1000000,10 lswrite,17time,170d,298,ux,0

18、.03allsel,all KBC,0allsel,all NSUBST,200,1000000,10 lswrite,18time,180d,298,ux,-0.03allsel,all KBC,0allsel,all NSUBST,200,1000000,10 lswrite,19time,190d,298,ux,0.03allsel,all KBC,0allsel,all NSUBST,200,1000000,10 lswrite,20time,200d,298,ux,-0.03allsel,all KBC,0allsel,all NSUBST,200,1000000,10 lswrit

19、e,21time,210d,298,ux,0.045allsel,all KBC,0allsel,all NSUBST,300,1000000,10 lswrite,22lssolve,1,22,1命令流：1、单调水平荷载作用下的命令流：建模：!mono brick wall!solid65-整体式建模!*Finish/clear/units,si/com,Structural/config,nres,400000/prep7/title,mono-brick-wall!*depth_sup=0.24 !弹性支垫240mm!单元属性!for brick, mortar and leveling

20、 coatet,1,solid65!*KEYOPT,1,1,0KEYOPT,1,5,0KEYOPT,1,6,0KEYOPT,1,7,1!for elastic supportet,2,solid45!*-砌体材料-!MU10,M5砌体材料属性mp,prxy,1,0.15mp,dens,1,1700mp,ex,1,0.24e10!砌体屈服准则TB,MKIN,1TBTEMP,strainTBdata,1,0.2E-3,1.0E-3,2.0E-3,3.0E-3,4.8E-3TBTEMP,!TBDATA,1,0.48E6,0.82E6,1.32E6,1.5E6,1.32E6TBDATA,1,0.48E

21、6,1.31E6,2.11E6,2.4E6,2.11E6!/XRANGE,0,0.02!TBPLOT,MKIN,1!砌体破坏准则!hntrl=0.13E6hntrl=0.21E6tb,concr,1,4,tbdata,0.2,0.9,hntrl,-1 !不考虑压碎!*-弹性支撑-!弹性支撑暂取钢筋材料属性mp,ex,2,2.0e11mp,dens,2,7.600 mp,prxy,2,0.30!real constantsr,1!*-modeling-!geometry modelblock,0,3.12,0,0.24,0,3.12block,-0.24,3.12,0,0.24,3.12,3.3

22、6Vsel,s,volu,1,2,1$aslv,s$lsla,slesize,all,0.24Vsel,s,volu,1$vatt,1,1,1, !brick wallVsel,s,volu,2$vatt,2,1,2, !brick wallvsel,all !必须再次选择所有单元VSWEEP,ALL savenumcmp,allallsel!*/device,vector,1/eshape,1!*-耦合-allsel,all!elastic support nodes setesel,s,type,2$nsle,s,all$nsel,r,loc,z,3.12nsel,u,loc,x,-0.2

23、4$cm,slavenode,node!other node setesel,s,type,1$nsle,s,all$cm,masternode,node/input,ucouple,macsavefinish耦合文件ucouple,mac：!*-开始-allsel !最好保留这句命令!*将从属节点编号依次存入数组*cmsel,s,slavenode*get,count1_node,node,0,count*del,slave_node*dim,slave_node,array,count1_node*get,slave_node(1),node,0,num,min*do,i,2,count1

24、_nodeslave_node(i)=ndnext(slave_node(i-1)*enddo !*将主节点编号依次存入数组*allselcmsel,s,masternode*get,count2_node,node,0,count*del,master_node*dim,master_node,array,count2_node*get,master_node(1),node,0,num,min*do,i,2,count2_nodemaster_node(i)=ndnext(master_node(i-1)*enddo!*将与从属节点耦合的节点数组初始化*del,cp_node*dim,cp

25、_node,array,count1_node*do,i,1,count1_nodecp_node(i)=0*enddo!*开始选择程序*allselcmsel,s,masternode*do,i,1,count1_node kk=1 k=1 *dowhile,kk k=nnear(slave_node(i)nsel,s,cp,allkk=nsel(k)+0.001 allselcmsel,s,masternodensel,u,node,kcm,masternode,node *enddo cp_node(i)=k *enddo!*选择完毕*!*开始耦合*allsel,all/prep7*do

26、,i,1,count1_nodecp,next,UX,slave_node(i),cp_node(i)cp,next,UY,slave_node(i),cp_node(i)cp,next,UZ,slave_node(i),cp_node(i)*enddo!*耦合完毕*求解方法NR法：brick wall NR solution!displacement load!用NR法!*-solution-/soluantype,0!-constraint-nsel,s,loc,z,0d,all,all!*esel,s,type,2$nsle,s,all$nsel,r,loc,x,-0.24d,all,u

27、y!*!esel,s,type,2$nsle,s,all$nsel,r,loc,x,-0.24!d,all,uzlumpm,onsolcontrol,onpred,onlnsrch,onautots,1 !打开自动时间步控制ncnv,2 !如果不收敛时结束而不退出compression=0.24E7!*-load steps-!*-1st-acel,9.8nsel,s,loc,z,3.36$nsel,r,loc,x,0.001,3.119esln,s,0,allsfe,all,6,pres,0,0.03*compressionallsel,all!*OUTRES,ERASEOUTRES,ALL

28、,ALLNSUBST,2,200,1neqit,15KBC,0nlgeom,1cnvtol,f,0.01,2,0.05allsellswrite,1!*-2nd step-nsel,s,loc,x,-0.24!esln,s,0,all!sfe,all,4,pres,0,60*0.0593E6!d,all,ux,2.79E-3d,all,ux,1.0E-4allsel,all!*OUTRES,ERASEOUTRES,ALL,ALLNSUBST,200,2000,100neqit,15KBC,0nlgeom,1cnvtol,f,0.05,2,0.05allsellswrite,2!*-3rd st

29、ep-nsel,s,loc,x,-0.24!esln,s,0,all!sfe,all,4,pres,0,60*0.0593E6!d,all,ux,2.79E-3d,all,ux,2.5E-4allsel,all!*OUTRES,ERASEOUTRES,ALL,ALLNSUBST,200,2000,100neqit,15KBC,0nlgeom,1cnvtol,f,0.09,2,0.25allsellswrite,3!*-4th step-nsel,s,loc,x,-0.24!esln,s,0,all!sfe,all,4,pres,0,60*0.0593E6!d,all,ux,2.79E-3d,a

30、ll,ux,4.0E-3allsel,all!*OUTRES,ERASEOUTRES,ALL,ALLNSUBST,200,2000,100neqit,15KBC,0nlgeom,1cnvtol,f,0.1,2,0.5allsellswrite,4!*allsel lssolve,1,4,1FINISH也可以用弧长法，不过没有一定经验这比较难控制：!mono brick wall-1 arclength solution!displacement load!*-solution-/soluantype,0!-constraint-nsel,s,loc,z,0d,all,all!*esel,s,t

31、ype,2$nsle,s,all$nsel,r,loc,x,-0.24d,all,uy!*lumpm,onsolcontrol,onncnv,2 !如果不收敛时结束而不退出compression=0.24E7!*-load steps-!*-first step-acel,9.8nsel,s,loc,z,3.36$nsel,r,loc,x,0.001,3.12esln,s,0,allsfe,all,6,pres,0,0.03*compressionallsel,all!*OUTRES,ERASEOUTRES,ALL,ALLarclen,on,1E-5, !使用弧长法NSUBST,200neqi

32、t,15KBC,0nlgeom,1cnvtol,f,0.1,2,0.5allsel,alllswrite,1!*-second step-esel,s,type,2$nsle,s,all$nsel,r,loc,x,-0.24d,all,uz!*nsel,s,loc,x,-0.24!esln,s,0,all!sfe,all,4,pres,0,60*0.0593E6d,all,ux,2.50E-3!d,all,ux,3.51E-3allsel,all!*OUTRES,ERASEOUTRES,ALL,ALLarclen,on,1E-5, !使用弧长法kbc,0NSUBST,250!arctrm,u,

33、0.0028,313,uxneqit,15nlgeom,1!cnvtol,f,0.005,2,0.01!cnvtol,f,0.05,2,0.5cnvtol,f,0.1,2,0.5allsellswrite,2!*-third step-esel,s,type,2$nsle,s,all$nsel,r,loc,x,-0.24d,all,uz!*nsel,s,loc,x,-0.24!esln,s,0,all!sfe,all,4,pres,0,60*0.0593E6!d,all,ux,2.79E-3!d,all,ux,3.18E-3d,all,ux,3.00E-3allsel,all!*OUTRES,

34、ERASEOUTRES,ALL,ALLarclen,on,1E-7, !使用弧长法kbc,0NSUBST,2000!arctrm,u,0.0028,313,uxneqit,15nlgeom,1!cnvtol,f,0.005,2,0.01!cnvtol,f,0.05,2,0.5cnvtol,f,0.5,2,0.8allsellswrite,3allsel!*-fourth step-esel,s,type,2$nsle,s,all$nsel,r,loc,x,-0.24d,all,uz!*nsel,s,loc,x,-0.24!esln,s,0,all!sfe,all,4,pres,0,60*0.0

35、593E6d,all,ux,3.51E-3allsel,all!*OUTRES,ERASEOUTRES,ALL,ALLarclen,on,1E-7, !使用弧长法kbc,0NSUBST,300!arctrm,u,0.0028,313,uxneqit,15nlgeom,1!cnvtol,f,0.005,2,0.01!cnvtol,f,0.05,2,0.5cnvtol,f,0.6,2,0.9allsellswrite,4allsel!*lssolve,1,4,1FINISH后处理：/post26esel,s,type,1eplotlines,5000nsol,2,326,u,x,ux!nsol,2

36、,313,u,x,ux*do,i,1,14jj=node(i-1)*0.24,0.24,0)kk=node(i-1)*0.24,0,0)! ll=node(225.5+(i-1)*225.5,3300,0)rforce,3,jj,f,x,fxadd,6,3,6rforce,4,kk,f,x,fxadd,6,4,6! rforce,5,ll,f,x,fx!add,6,5,6*enddoprod,7,2,1000prod,8,6,-1/1000/axlab,x,Displacement(mm)/axlab,y,F(kN)/XRANGE,0,4/YRANGE,0,100xvar,7plvar,8!r

37、force,5,340,f,x,fx!esol,5,87,221,f,x,fx2、循环水平荷载作用下的命令流：出求解文件不同外，其他都相同；!cyclic NR solution!displacement load!*-solution-/soluantype,0!-constraint-nsel,s,loc,z,0d,all,all!*esel,s,type,2$nsle,s,all$nsel,r,loc,x,-0.24d,all,uy!*esel,s,type,2$nsle,s,all$nsel,r,loc,x,3.36d,all,uy!*lumpm,onsolcontrol,onpred

38、,onlnsrch,onautots,1 !打开自动时间步控制ncnv,2 !如果不收敛时结束而不退出compression=0.24E7!*-load steps-!*-1st step-acel,9.8nsel,s,loc,z,3.36$nsel,r,loc,x,0.001,3.119esln,s,0,allsfe,all,6,pres,0,0.03*compressionallsel,all!*OUTRES,ERASEOUTRES,ALL,ALLNSUBST,200,2000,10neqit,15KBC,0nlgeom,1cnvtol,f,0.1,2,0.5allsel,alllswri

39、te,1!*-初裂荷载20%做1次循环-!*-用NR法-!*-2nd step-esel,s,type,2$nsle,s,all$nsel,r,loc,x,-0.24d,all,uz!*esel,s,type,2$nsle,s,all$nsel,r,loc,x,3.36d,all,uz!*nsel,s,loc,x,-0.24!esln,s,0,all!sfe,all,4,pres,0,60*0.0593E6d,all,ux,1.48E-4allsel,all!*OUTRES,ERASEOUTRES,ALL,ALLNSUBST,20,2000,10neqit,15NROPT ,FULL,OFFK

40、BC,0nlgeom,1cnvtol,f,0.1,2,0.5allsellswrite,2!*-3rd step-nsel,s,loc,x,-0.24ddele,all,uxnsel,s,loc,x,3.36d,all,ux,-1.48E-4allsel,all!*OUTRES,ERASEOUTRES,ALL,ALLNSUBST,40,2000,20neqit,15NROPT ,FULL,OFFKBC,0nlgeom,1cnvtol,f,0.1,2,0.5allsellswrite,3!*-4th step-nsel,s,loc,x,3.36ddele,all,uxnsel,s,loc,x,-

41、0.24d,all,ux,1.48E-4allsel,all!*OUTRES,ERASEOUTRES,ALL,ALLNSUBST,40,2000,20neqit,15NROPT ,FULL,OFFKBC,0nlgeom,1cnvtol,f,0.1,2,0.5allsellswrite,4!*-one cycle-!*-初裂荷载50%做1次循环-!*-用NR法-!*-5th step-nsel,s,loc,x,-0.24ddele,all,uxnsel,s,loc,x,-0.24d,all,ux,2.85E-4allsel,all!*OUTRES,ERASEOUTRES,ALL,ALLNSUBS

42、T,100,2000,10neqit,15NROPT ,FULL,OFFKBC,0nlgeom,1cnvtol,f,0.1,2,0.5allsellswrite,5!*-6th step-nsel,s,loc,x,-0.24ddele,all,uxnsel,s,loc,x,3.36d,all,ux,-2.85E-4allsel,all!*OUTRES,ERASEOUTRES,ALL,ALLNSUBST,200,2000,30neqit,15NROPT ,FULL,OFFKBC,0nlgeom,1cnvtol,f,0.1,2,0.5allsellswrite,6!*-7th step-nsel,s,loc,x,3.36ddele,all,uxnsel,s,loc,x,-0.24d,all,ux,2.85E-4allsel,all!*OUTRES,ERASEOUTRES,ALL,ALLNSUBST,200,2000,30neqit,15NROPT