[FredJP]

Dear Forum Members,

I am trying to set up a script for modeling structural elasticity, nonlinear plasticity and creep simultaneously.
I noticed that I will have to ramp up applied stresses in several steps, otherwise my solution seems not to converge.

I tried to make a *DO loop, however for some reason wihtin this loop variables seem to change only one time. In the second loop-run all variables seem to not exist. I read something about the NROPT and "In some rare cases, switching between the symmetric and unsymmetric options can cause a system core dump...". Does it have anythign to do with my problem here?

For this issue, please see line 122 till 134. The variables in L132-L134 seem to be affected.

Thanks in advance for your help.

FINISH
/CLEAR


CTIME=3000 !s
CTEMP=22  !°C
KELVIN=273.15 !-°C
ATEMP=CTEMP+KELVIN
STEPG=0
MAXS=3
STRESSL=-100E6
STIME=0.01
TG=322 !°C


C1=1.34863172395486E-14
C2=1.500846380745644
C3=-0.711699049863429
C4=1436.771814880534

C5=294322013.4109269
C6=-520664.888308746
C7=1393998904.70262
C8=-2120691.36007548
C9=99751034.4580581
C10=-33226.0683057575
C11=109.036533811756




S0 = 1
R0 = C7+ATEMP*C8
Rinf = C9+ATEMP*C10
b=C11

YOUNG=9.3E9-(CTEMP-22)*28E6



KEYW,PR_STRUC,1
/COM,Structual
/PREP7
!*
!Element setting
ET,1,PLANE183




!Material setting
MP,EX,1,YOUNG !Youngs modulus
MP,NUXY,1,0 !Poisson ratio


TB,NLISO,1,1,4,VOCE
TBDATA,,S0,R0,Rinf,b



TB,CREEP,1,1,4,6
TBDATA,,C1,C2,C3,C4 !C1-C4



!Temperature setting
TOFFST,KELVIN

!Make rectangle model
RECTNG,0,1,0,1


!Mesh setting
AESIZE,ALL,1, !Size of mesh
MSHAPE,0,2D
MSHKEY,0
AMESH, ALL

FINISH



/SOLU

!Transient analysis
ANTYPE,4
TRNOPT,FULL
LUMPM,0
!Time setting
TIME,STIME
AUTOTS, OFF
DELTIM,0.001,0.001,0.001
OUTRES,ALL,ALL
!Depend on creep rate
RATE,1
!*
!Apply temperature
BFA,1,TEMP,CTEMP
!Displacement setting
DL,1,,UX,0
DL,1,,UY,0
DL,2,,UX,0
DL,3,,UX,0
DL,4,,UX,0

SSTRESS = STRESSL/200

SFL,3,PRES,SSTRESS
!*
/SOL





SOLVE
FINISH




*DO,j,1,MAXS,1



/SOLU
!Transient analysis
ANTYPE,TRANS,REST,STEPG+1,,CONTINUE
NROPT,FULL,,,


SSTRESS=STRESSL/(MAXS-STEPG)
STEPG=STEPG+1
STIME=STIME+0.01




!Time setting
TIME,STIME
AUTOTS, OFF
DELTIM,0.001,0.001,0.001
!OUTRES,ALL,ALL
!Depend on creep rate
RATE,1
!*
!Apply temperature
BFA,1,TEMP,CTEMP
!DEFINE LOADS
DL,1,,UX,0
DL,1,,UY,0

DL,2,,UX,0
DL,3,,UX,0
DL,4,,UX,0



SFL,3,PRES,SSTRESS


!*
SOLVE
FINISH

*ENDDO

/DSCALE, ALL, 50