*HEADING NAFEMS BENCHMARK EXAMPLE 3DNLG-3 ELEMENT:B32H ELASTIC LATERAL BUCKLING OF A RIGHT ANGLE FRAME UNDER IN-PLANE END MOMENTS APPLY PERTURBATION LOAD AND SLIGHT ROTATION *NODE 1,-169.7056275,0.0 21,0.0,169.7056275,0.0 *NGEN 1,21 *ELEMENT,TYPE=B32H 1,1,2,3 *ELGEN,ELSET=BEAM 1,10,2,1 *BEAM GENERAL SECTION,SECTION=RECT,ELSET=BEAM 0.6,30 0.0,0.0,-1.0 71240,27190.84 *AMPLITUDE,NAME=CONSTANT,TIME=STEP 0.0,1.0,1.0,1.0 *RESTART,WRITE *STEP,NLGEOM,INC=10 put initial side load on frame *STATIC *BOUNDARY 21,XSYMM 1,2,5,0.0 1,6,6,0.0 *CLOAD 21,3,0.01 *CONTROLS, PARAMETERS=FIELD ,0.0, *NSET,NSET=NOUT 1,21 *NSET,NSET=A 1, *NSET,NSET=B 21, *NODE FILE,NSET=NOUT U, RF, *OUTPUT,FIELD *NODE OUTPUT,NSET=NOUT U, RF, *NODE PRINT,NSET=A,F=1 UR3,RM3 *NODE PRINT,NSET=B,F=1 U3, *END STEP *STEP,NLGEOM,INC=45 get initial lateral buckling *STATIC,RIKS 0.001,1.0,,,1.0 *MONITOR,NODE=1,DOF=6 *BOUNDARY,TYPE=VELOCITY,OP=NEW 1,2,5,0.0 1,6,6,0.08 21,XSYMM *NODE PRINT,NSET=A,F=1 UR3,RM3 *NODE PRINT,NSET=B,F=1 U3, *NODE FILE,NSET=NOUT U, RF, *OUTPUT,FIELD *NODE OUTPUT,NSET=NOUT U, RF, *END STEP