*HEADING
: SIMPLE CONTACT TEST WITHOUT FRICTION, SMALL SLIDING, RIGID SURFACE
*NODE, NSET=BLOCK
 1,  4., 1., 4.
 2,  4., 1., 1.
 3,  2., 1., 1.
 4,  2., 1., 4.
 5,  4., 3., 4.
 6,  4., 3., 1.
 7,  2., 3., 1.
 8,  2., 3., 4.
 9,  4., 1., 2.5
 10, 3., 1., 1.
 11, 2., 1., 2.5
 12, 3., 1., 4.
 13, 4., 3., 2.5
 14, 3., 3., 1.
 15, 2., 3., 2.5
 16, 3., 3., 4.
 17, 4., 2., 4.
 18, 4., 2., 1.
 19, 2., 2., 1.
 20, 2., 2., 4.
 21, 3., 2., 2.5
 22, 3., 1., 2.5
 23, 3., 3., 2.5
 24, 4., 2., 2.5
 25, 3., 2., 1.
 26, 2., 2., 2.5
 27, 3., 2., 4.
*NODE
 9999, 0., 0., 0.
*NSET,NSET=TOP
 5,6,7,8,13,14,15,16,23
*NSET,NSET=BOT
 1,2,3,4,9,10,11,12,22
*NSET,NSET=LEFT
 3,4,7,8,11,15,19,20,26
*NSET,NSET=RIGHT
 1,2,5,6,9,13,17,18,24
*NSET,NSET=MID
 9,11,13,15,21,22,23,24,26
*ELEMENT, TYPE=C3D27, ELSET=BLOCK
 1, 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,
 16,17,18,19,20,21,22,23,24,25,26,27
*surface,NAME=ASURF
BLOCK,S1
*CONTACT PAIR,INTERACTION=SMOOTH
ASURF,BSURF
*SURFACE INTERACTION,NAME=SMOOTH
*FRICTION
0.0, 
*SOLID SECTION, ELSET=BLOCK, MATERIAL=SOFT
*MATERIAL, NAME=SOFT
*ELASTIC
 30.E6, 0.3
*rigid body,analytical surface=BSURF,REFNODE=9999
*surface,TYPE=CYLINDER,NAME=BSURF
 0., 0., 10.,   10., 0., 10.
 0., 0., -10.
 START, 0., 0.
 LINE, 10., 0.
**
** Step 1:  Bring block into contact and push against rigid surface
**
*STEP,AMP=RAMP
*STATIC
 1., 1., 0.01
*CONTROLS,PARAMETERS=FIELD
 0.000001,
*BOUNDARY
 1, 1
 2, 1
 9, 1
 9, 3
 9999, 1,6
 TOP,2,, -1.00001
*CONTACT PRINT,SECONDARY=ASURF,MAIN=BSURF
*OUTPUT,FIELD
*CONTACT OUTPUT,VARIABLE=PRESELECT,SECONDARY=ASURF,MAIN=BSURF
*OUTPUT,FIELD
*ELEMENT OUTPUT
S,
*OUTPUT,FIELD
*NODE OUTPUT
U,
*END STEP
**
** Step 2: Apply normal load on top surface of block
**
*STEP,AMP=RAMP
*STATIC
 1., 1., 0.00001
*BOUNDARY,OP=NEW
 1, 1
 2, 1
 9, 3
 9, 1
 9999, 1,6
*DLOAD
 BLOCK, P2, 100.E3
*OUTPUT,FIELD
*CONTACT OUTPUT,VARIABLE=PRESELECT,SECONDARY=ASURF,MAIN=BSURF
*OUTPUT,FIELD
*ELEMENT OUTPUT
S,
*OUTPUT,FIELD
*NODE OUTPUT
U,
*END STEP
**
** Step 3: Slide block by fixing one end and pulling on the other
**
*STEP,AMP=RAMP,NLGEOM,INC=20
*STATIC
 0.1, 1., 0.001
*BOUNDARY,OP=NEW
 LEFT,1,,-1.0
 RIGHT,1
 MID,3
 9999, 1,6
*OUTPUT,FIELD
*CONTACT OUTPUT,VARIABLE=PRESELECT,SECONDARY=ASURF,MAIN=BSURF
*OUTPUT,FIELD
*ELEMENT OUTPUT
S,
*OUTPUT,FIELD
*NODE OUTPUT
U,
*END STEP
**
** step 4: change surface friction
**
*STEP,NLGEOM
*STATIC
1.0,1.0
*CHANGE FRICTION,INTERACTION=SMOOTH
*FRICTION
0.0, 
*ENDSTEP
**
** step 5: slide to the left w/ friction
**
*STEP,NLGEOM
*STATIC
*BOUNDARY,OP=NEW
 LEFT,1,,-1.0
 RIGHT,1,,-1.0
 MID,3
 9999, 1,6
*OUTPUT,FIELD
*ELEMENT OUTPUT
S,
*OUTPUT,FIELD
*NODE OUTPUT
U,
*OUTPUT,FIELD
*CONTACT OUTPUT,VARIABLE=PRESELECT,SECONDARY=ASURF,MAIN=BSURF
*CONTACT PRINT,SECONDARY=ASURF,MAIN=BSURF
*PRINT,CONTACT=YES
*ENDSTEP