*HEADING
 DYNAMIC ANALYSIS COMPARISON  B31
 (exact rotary inertia formulation versus isotropic
  compare to b31_dyn_iso)
*NODE
*NSET,NSET=ENDS
*ELSET,ELSET=PR
*ELEMENT,TYPE=B31,ELSET=EALL
*MATERIAL,NAME=A1
*ELASTIC
30.E6,
*DENSITY
 .000728,
*BEAM SECTION,SECTION=RECT,MATERIAL=A1,ELSET=EALL,ROTARY INERTIA=EXACT
1. , 2.
*BOUNDARY
11, 2, 6
*AMPLITUDE,TIME=STEP TIME,VALUE=RELATIVE,NAME=EQ
0.0,0.0,0.25,1.0,0.5,0.0,0.75,-1.0,
1.0,0.0,
**
*STEP,INC=200
 Sine type input
*DYNAMIC,ALPHA=0.0,direct
.005,1.0
*BOUNDARY,TYPE=ACCELERATION,AMPLITUDE=EQ
11,  1,1,  386.09
*PRINT,RESIDUAL=NO,FREQUENCY=50
*EL PRINT,ELSET=PR,FREQUENCY=50
S,E
*NODE PRINT,FREQUENCY=50
U,
*NODE FILE,NSET=ENDS
U,V,A
*ENERGY FILE,FREQUENCY=1
*OUTPUT,FIELD, FREQUENCY=1,OP=NEW
*NODE OUTPUT,NSET=ENDS
U,V,A
*OUTPUT,HISTORY, FREQUENCY=1,OP=NEW
*NODE OUTPUT,NSET=ENDS
U,V,A
*ENERGY OUTPUT,VARIABLE=ALL
*END STEP