*heading
 test bergstrom-boyce, relaxation during uploading and unloading
 relaxation strain=-0.6, strain rate=-0.1/s
 material: Chloroprene Rubber (15 pph carbon black)
*node
1,
2, 0.014
3, 0.014, 0.013
4, 0.0,   0.013
*element,type=cax4,elset=eall
1,1,2,3,4
*solid section,elset=eall,material=hyster
*material,name=hyster
*hyperelastic,arruda-boyce,MODULI=LONG TERM
0.6,2.8284,0.01
*hysteresis
1.6,0.9516,4.,-1.0
*boundary
1,1,1,
3,2,2,
4,1,2,
**
** STEP #1: load to strain=-0.6, strain rate=-0.1
**
*DIAGNOSTICS,NONHYBRID=WARNING
*step,nlgeom,inc=1000,unsymm=yes
*static
0.5,6.,,0.5
*boundary
1,2,2,0.005865
2,2,2,0.005865
*el print
s, 
le, 
*node print
rf,u
*OUTPUT,FIELD
*ELEMENT OUTPUT
s,le
*OUTPUT,FIELD
*NODE OUTPUT
u,rf
*end step
**
** STEP #2: relax (uploading) for 1000 sec. at strain=-0.6
**
*step,nlgeom,inc=1000,unsymm=yes
*static
0.01,1000.
*boundary
1,2,2,0.005865
2,2,2,0.005865
*end step
**
** STEP #3: load to strain=-0.8, strain rate=-0.1
**
*step,nlgeom,inc=1000,unsymm=yes
*static
0.1,2.0,,0.2
*boundary
1,2,2,0.007159
2,2,2,0.007159
*el print
s, 
le, 
*node print
rf,u
*OUTPUT,FIELD
*ELEMENT OUTPUT
s,le
*OUTPUT,FIELD
*NODE OUTPUT
u,rf
*end step
**
** STEP #4: unload to strain=-0.6, strain rate=0.1
**
*step,nlgeom,inc=1000,unsymm=yes
*static
0.1,2.0,,0.2
*boundary
1,2,2,0.005865
2,2,2,0.005865
*el print
s, 
le, 
*node print
rf,u
*OUTPUT,FIELD
*ELEMENT OUTPUT
s,le
*OUTPUT,FIELD
*NODE OUTPUT
u,rf
*end step
**
** STEP #5: relax (unloading) for 1000 sec. at strain=-0.6
**
*step,nlgeom,inc=1000,unsymm=yes
*static
0.01,1000.
*boundary
1,2,2,0.005865
2,2,2,0.005865
*end step