线形粘弹性UMAT

1、深入剖析UMA线形粘弹性体liuxi ongsimwe 用户名：LXCAD摘要本文介绍了 线形粘弹体的 UMAT程序说明，与 ZHANG chunyu 起学习UMAT为姐 妹篇。UMAT其实并不难学，你要把握几点即可：1，必须提供准确的 雅可比距阵，程序收敛速度快2，必须用增量法更新应力? must update the stresses and solution-dependentstate variables totheir values at the end of the in creme nt for which it is called;? must provide the mate

2、rial Jacobia n matrix3,与本构方程相关的状态变量必须更新把我分析的子程序过程多读几遍，相关的弹性力学，朔性力学概念弄懂，可能就理解更为清晰！ 我的目的就是让大家学的轻松！请大家鼓励！三单元体的固体模型（线形粘弹性）下图为虎克体和开尔文体的串联一维方向的应力与应变的行为 + （Ei：艮）=1+；/足 + （L/Ei + l/Eo）推广到实体Gf +汕JQ-=人班 +r + 幼二口F + 沖5 =+ 沁其中*常=工* + 州+ 彳”PROPS(1)PROPS(2)PROPS(3)PROPS(4)PROPS(5)SUBROUTINE UMAT(STRESS,STATEV,DDS

3、DDE,SSE,SPD,SCD,1 RPL,DDSDDT,DRPLDE,DRPLDT,2 STRAN,DSTRAN,TIME,DTIME,TEMP,DTEMP,PREDEF,DPRED,CMNAME,3 NDI,NSHR,NTENS,NSTATV,PROPS,NPROPS,COORDS,DROT,PNEWDT,4 CELENT,DFGRDO,DFGRD1,NOEL,NPT,LAYER,KSPT,KSTEP,KINC)CINCLUDE ABA_PARA M.INCCCHARACTER*80 CMNAMEDIMENSION STRESS(NTENS),STATEV(NSTATV),1 DDSDDE

4、(NTENS,NTENS),2 DDSDDT(NTENS),DRPLDE(NTENS),3 STRAN(NTENS),DSTRAN(NTENS),TIME(2),PREDEF(1),DPRED(1),4 PROPS(NPROPS),COORDS(3),DROT(3,3),DFGRDO(3,3),DFGRD1(3,3)DIMENSION DSTRES(6),D(3,3)CC EVALUATE NEW STRESS TENSORCEV = 0.DEV = 0.DO K1=1,NDIEV = EV + STRAN(K1)!直接应力和vxxyyxyDEV = DEV + DSTRAN(K1)!直接增量

5、应力和vxxyyxyEND DOCTERM1 = .5*DTIME + PROPS(5)!t V2TERM1I = 1./TERM1! 1t2vTERM2 = (.5*DTIME*PR0PS+PROPS(3)*TERM1I*DEV_tii HtTERM3 = (DTIME*PROPS(2)+2.*PROPS(4)*TERM1Ill2 t 2 tC更新正应力DO K1=1,NDIDSTRES(K1) = TERM2+TERM3*DSTRAN(K1)1 +DTIME*TERM1I*(PROPS(1)*EV2 +2.*PROPS(2)*STRAN(K1)-STRESS(K1)本构方程程序执行:t2S

6、TRESS(K1) = STRESS(K1) + DSTRES(K1)END DOC更新剪应力t TERM2=tV2TERM2 = (.5*DTIME*PROPS(2) + PROPS(4)*TERM1II1 = NDIDO K1=1,NSHRI1 = I1+1本构方程I“fl _程序执行:xy2tv2xy + t*(xyxyDSTRES(II) = TERM2*DSTRAN(I1)+1 DTIME*TERM1I*(PROPS(2)*STRAN(I1)-STRESS(I1)STRESS(I1) = STRESS(I1)+DSTRES(I1)END DOC雅可比距阵开始C CREATE NEW

7、JACOBIANTERM2=*( t(一 )2)t2V2TERM2 = (DTIME*(.5*PROPS(1)+PROPS(2)+PROPS(3)+1 2.*PROPS(4)*TERM1ITERM3tTERM3 = (.5*DTIME*PROPS(1)+PROPS(3)*TERM1IDO K1=1,NTENSDO K2=1,NTENSDDSDDE(K2,K1) = 0.END DOEND DOCDO K1=1,NDIDDSDDE(K1,K1) = TERM2END DOC填充距阵如下位置term2 term3 term3term3 term2 term3term3 term3 term2DO

8、K仁 2,NDIN2 = K1-1DO K2=1,N2DDSDDE(K2,K1) = TERM3DDSDDE(K1,K2) = TERM3END DOEND DOTERM2 =)TERM2 = (.5*DTIME*PROPS(2)+PROPS(4)*TERM1II1 = NDI川1=3按新TERM2填充距阵如下位置term 2term2term2DO K1=1,NSHR!按剪切力运行 3次I1 = I1+1DDSDDE(I1,I1) = TERM2END DO小结：雅可比距阵填充完毕直接应力部分C关于物质能量的增长C TOTAL CHANGE IN SPECIFIC ENERGYCE E (亍

9、)TDE = 0.DO K1=1,NTENSTDE = TDE + (STRESS(K1)+.5*DSTRES(K1)*DSTRAN(K1)END DOCC关于朔性能量的增长g +壬罚)D邛切二三“C CHANGE IN SPECIFIC ELASTIC STRAIN ENERGYCTERM1 = PROPS(1) + 2.*PROPS(2) !TERM1= 2填充距阵如下位置term1term1term1DO K1=1,NDID(K1,K1) = TERM1END DO填充距阵如下位置DO K1=2,NDIN2 = K1-1DO K2=1,N2D(K1,K2) = PROPS(1)D(K2,

10、K1) = PROPS(1)END DOEND DO外循环数内循 环数K1K2TERM1TERM2DEE1111D(1,1)* (1)D(1,1)*(1)(D13 3D12 2D11 1D133 D122 D111 )2* (1)212D(1,2)* (2) +D(1,1)* (1)D(1,2)*(2) +D(1,1)*(1)313D(1,3)* (3) +D(1,2)* (2) +D(1,1)* (1)D(1,3)*(3) +D(1,2)*(2) +D(1,1)*(1)2121D(2,1)* (1)D(2,1)*(1)(D13 3 D12 2 D11 1D133D122 D1112 )* (

11、1)(D23 3 D22 2 D 21 1D233 D 222D211)2* (2)222D(2,2)* (2) +D(2,1)* (1)D(2,2)*(2) +D(2,1)*(1)323D(2,3)* (3) +D(2,2)* (2) +D(2,1)* (1)D(2,3)*(3) +D(2,2)*(2) +D(2,1)*(1)3131D(3,1)* (1)D(3,1)*(1)(D133D122D111D133D122D111232D(3,2)* (2) +D(3,1)* (1)D(3,2)*(2) +D(3,1)*(1)2 )* (1)(D23 3 D22 2 D 21 1D233D222D

12、2112 )* (2)(D333D322D311D333 D322D311)2*(3)333D(3,3)* (3) +D(3,2)* (2) +D(3,1)* (1)D(3,3)*(3) +D(3,2)*(2) +D(3,1)*(1)分析以下循环，实质为能量变化，力*位移DEE = 0.DO K1=1,NDITERM1 = 0.TERM2 = 0.DO K2=1,NDITERM1 = TERM1 + D(K1,K2)*STRAN(K2)TERM2 = TERM2 + D(K1,K2)*DSTRAN(K2)END DODEE = DEE + (TERM1+.5*TERM2)*DSTRAN(K1)END DO剪切应力部分L1K1DDE41*( 4 才 425245*( 4)4*( 5)52 263* / 、 * ( 5 * / 6 (4丿4(5小丿5(6小丿62