*HEADING
PRESSURIZING OF A FLAT RUBBER PLATE (CAXA8H1)
WITH UNIFORM PRESTRESS (RADIAL AND CIRCUMFERENTIAL)
*NODE
*NGEN,LINE=P
*ELEMENT,TYPE=CAXA8H1,ELSET=ONE,OFFSET=1000
*ELGEN,ELSET=ALL
*NSET,NSET=CENTER
*EQUATION
*ELSET,ELSET=ONE
*SOLID SECTION,MATERIAL=A1,ELSET=ALL
*MATERIAL,NAME=A1
*HYPERELASTIC,N=1
80.0,20.0
*INITIAL CONDITIONS,TYPE=STRESS
ALL, 50.,0.,50.
*RESTART,WRITE,FREQUENCY=2
*STEP,NLGEOM, UNSYMM=YES
 MAINTAIN PRESTRESS - THIS STEP IS FOR VERIFICATION PURPOSES OF INITIAL
 STRESSES IN HYPERELASTICITY
*STATIC
*BOUNDARY
CENTER,XSYMM
31,1,2
1031,1,2
*EL PRINT,FREQUENCY=5,ELSET=ALL
COORD , E
DG,
LOADS,
S,MISES
ENER,
*EL PRINT,FREQUENCY=1,ELSET=ONE,SUMMARY=NO
COORD , E
DG,
LOADS,
S,MISES
ENER,
*NODE FILE,NSET=CENTER
U ,RF
*OUTPUT,FIELD
*NODE OUTPUT,NSET=CENTER
U,RF
*EL FILE,FREQUENCY=2,ELSET=ONE
S,
LOADS,
*OUTPUT,FIELD,FREQ=2
*ELEMENT OUTPUT,ELSET=ONE
S,
LOADS,
*NODE PRINT
U,RF
*END STEP
*STEP,NLGEOM,INC=12, UNSYMM=YES
 APPLY PRESSURE TO RUBBER PLATE
*STATIC,RIKS
.01,1.0,.00001,1.0,1.0,1,1,10000.
CENTER,XSYMM
*DLOAD
ALL,P1,2.E+2
*MONITOR,NODE=21,DOF=2
*END STEP