*HEADING
: SIMPLE CONTACT TEST, FINITE SLIDING CONTACT WITHOUT FRICTION, RIGID 
** Contact Features Tested: 
**      permeable-impermeable pore pressure contact for pore pressure coupled contact
*NODE, NSET=BLOCK
 1,  4., 1., 4.
 2,  4., 1., 1.
 3,  2., 1., 2.
 4,  2., 1., 3.
 5,  4., 3., 4.
 6,  4., 3., 1.
 7,  2., 3., 2.
 8,  2., 3., 3.
*NODE
 9999, 0., 0., 0.
*NSET,NSET=TOP
 5,6,7,8
*NSET,NSET=BOT
 1,2,3,4
*NSET,NSET=LEFT
 3,4,7,8
*NSET,NSET=RIGHT
 1,2,5,6
*ELEMENT, TYPE=C3D8RP, ELSET=BLOCK
 1,  1,2,3,4,5,6,7,8
*SOLID SECTION, ELSET=BLOCK, MATERIAL=SOFT
*HOURGLASS STIFFNESS
1.E7
*MATERIAL, NAME=SOFT
*ELASTIC
 30.E6, 0.3
*DENSITY
10., 
*PERMEABILITY,SPECIFIC=1.0
1.e-4, 
*INITIAL CONDITIONS,TYPE=RATIO
BLOCK,1.0
*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.
*surface,NAME=ASURF
BLOCK,S1
*CONTACT PAIR,INTERACTION=SMOOTH
ASURF,BSURF
*SURFACE INTERACTION,NAME=SMOOTH
*FRICTION
0.0, 
**
** Step 1:  Bring block into contact and push against rigid surface
**
*STEP,AMP=RAMP
*SOIL,CONSOLIDATION
 0.1,1
*CONTROLS,PARAMETERS=FIELD
 0.000001,
*BOUNDARY
 1, 1
 2, 1
 2, 3
 9999, 1,6
 TOP, 2,, -1.00001
 TOP,8,8,1
*PRINT, CONTACT=YES
*CONTACT PRINT,SECONDARY=ASURF
*CONTACT FILE,SECONDARY=ASURF
*EL FILE
 S,
*NODE FILE,F=100
U, 
POR, 
*NODE PRINT
U,POR
*OUTPUT,FIELD
*NODE OUTPUT
U,POR
*ELEMENT OUTPUT
S,
*CONTACT OUTPUT,VARIABLE=PRESELECT,SECONDARY=ASURF
*END STEP
**
** Step 2: Apply normal load on top surface of block
**
*STEP,AMP=RAMP
*SOIL, CONSOLIDATION
 0.1,1
*BOUNDARY,OP=NEW
 1, 1
 2, 1
 2, 3
 9999, 1,6
 TOP,8,8,1
*DLOAD
 BLOCK, P2, 100.E3
*PRINT, CONTACT=YES
*CONTACT FILE,SECONDARY=ASURF
*EL FILE
 S,
*NODE FILE,F=100
U,POR
*NODE PRINT
U,POR
*END STEP
**
** Step 3: Slide block by fixing one end and pulling on the other
**
*STEP,AMP=RAMP,NLGEOM
*SOIL, CONSOLIDATION
 0.1, 1.
*BOUNDARY,OP=NEW
 LEFT,1,,-2.0
 RIGHT,1
 6,3
 9999, 1,6
 TOP,8,8,1
*CONTACT FILE,SECONDARY=ASURF
*EL FILE
 S,
*NODE FILE,F=100
U, 
*END STEP
**
** step 4: Steady state dynamics, direct analysis
**
*STEP
*STEADY STATE DYNAMICS,DIRECT
20,80,5
*BOUNDARY,OP=NEW
 1, 1
 2, 1
 2, 3
 9999, 1,6
 TOP,8,8,1
*DLOAD
 BLOCK, P2, 100.E3
*NODE FILE
U, 
RF, 
*EL FILE
E, 
S, 
*CONTACT FILE
*OUTPUT,FIELD
*NODE OUTPUT
U,
RF,
*ELEMENT OUTPUT
E,
S,
*CONTACT OUTPUT,VARIABLE=PRESELECT,SECONDARY=ASURF
*END STEP
**
** step 5: frequency extraction
**
*STEP
*FREQUENCY, eigensolver=lanczos, SIM=NO
17, , 
*BOUNDARY,OP=NEW
 1, 1
 2, 1
 2, 3
 9999, 1,6
 TOP,8,8,1
*MODAL FILE
*NODE FILE,F=0
*EL FILE,F=0
*NODE PRINT,F=0
*EL PRINT,F=0
*OUTPUT,FIELD,OP=NEW
*NODE OUTPUT
U,
*CONTACT FILE,FREQ=0
*END STEP
**
** step 6: Steady state dynamics, subspace projection 
**
*STEP
*STEADY STATE DYNAMICS,SUBSPACE PROJECTION,INTERVAL=RANGE
20,80,5
*DLOAD
 BLOCK, P2, 100.E3
*NODE FILE
U, 
*EL FILE
E, 
S, 
*OUTPUT,FIELD,OP=NEW
*NODE OUTPUT
U,
*ELEMENT OUTPUT
*CONTACT FILE
*END STEP