*HEADING
 NAFEMS BENCHMARK EXAMPLE 3DNLG-3  ELEMENT:B32H
 ELASTIC LATERAL BUCKLING OF A RIGHT ANGLE FRAME UNDER IN-PLANE END MOMENTS
 REMOVE PERTURBATION LOAD AND CONTINUE ROTATION
*RESTART,READ,STEP=2,ENDSTEP
*STEP,NLGEOM,INC=100
change side load to a much smaller value
*STATIC
*BOUNDARY,TYPE=VELOCITY,AMPLITUDE=CONSTANT,OP=MOD
1,6,6,0.0
*CLOAD,OP=NEW
21,3,1.0E-7
*END STEP
*STEP,NLGEOM,INC=121	
continue end rotation
*STATIC,RIKS
0.001,1.0
*MONITOR,NODE=1,DOF=6
*BOUNDARY,TYPE=VELOCITY,OP=NEW
21,1
21,5
21,6
1,2,5,0.0
1,6,6,6.2832
*CONTROLS,PARAMETER=FIELD,FIELD=ROTATION
0.0001,0.0001
*NODE PRINT,NSET=A,F=1
UR3,RM3
*NODE PRINT,NSET=B,F=1
U3, 
*NODE FILE,NSET=NOUT
U, 
RF, 
*END STEP