Abaqus-Umat线性随动强化子程序验证

        SMISES=(STRESS(1)-ALPHA(1)-STRESS(2)+ALPHA(2))**2     1  +(STRESS(2)-ALPHA(2)-STRESS(3)+ALPHA(3))**2     1  +(STRESS(3)-ALPHA(3)-STRESS(1)+ALPHA(1))**2        do K1=NDI+1,NTENS            SMISES=SMISES+SIX*(STRESS(K1)-ALPHA(K1))**2        enddo        SMISES=SQRT(SMISES/TWO)CC GET YIELD STRESS AND HARDENING MODULUSC        SYIELD=PROPS(3)        HARD=PROPS(4)CC DETERMINE IF ACTIVELY YIELDINGC        if(SMISES.gt.(ONE+TOLER)*SYIELD) then
CC ACTIVELY YIELDINGC SEPARATE THE HYDROSTATIC FROM THE DEVIATORIC STRESSC CALCULATE THE FLOW DIRECTIONC            SHYDRO=(STRESS(1)+STRESS(2)+STRESS(3))/THREE            do K1=1,NDI                flow(K1)=(STRESS(K1)-SHYDRO-ALPHA(K1))/SMISES            enddo            do K1=NDI+1,NTENS                flow(K1)=(STRESS(K1)-ALPHA(K1))/SMISES            enddoCC SOLVE FOR EQUIVALENT PLASTIC STRAIN INCREMENTC            DEQPL=(SMISES-SYIELD)/(HARD+EG3)CC UPDATE SHIFT TENSOR, ELASTIC AND PLASTIC STRAINS AND STRESSC            do k1=1,NDI                ALPHA(K1)=ALPHA(K1)+HARD*flow(K1)*DEQPL                EPLAS(K1)=EPLAS(K1)+THREE/Two*flow(K1)*DEQPL                EELAS(K1)=EELAS(K1)-THREE/Two*flow(K1)*DEQPL                STRESS(k1)=ALPHA(k1)+FLOW(k1)*SYIELD+SHYDRO            enddo            DO k1=NDI+1,NTENS                ALPHA(K1)=ALPHA(K1)+HARD*flow(K1)*DEQPL                EPLAS(K1)=EPLAS(K1)+THREE*flow(K1)*DEQPL                EELAS(K1)=EELAS(K1)-THREE*flow(K1)*DEQPL                STRESS(k1)=ALPHA(k1)+FLOW(k1)*SYIELD                          ENDDO