*HEADING
: SIMPLE CONTACT TEST, 3-D SMALL SLIDING, DEFORMABLE, C3D8
** Contact Features Tested:
**	*CONTACT INTERFERENCE, *FRICTION, *CHANGE FRICTION (mu=0 and mu=0.3),
**	*surface,type=node
*RESTART,WRITE, FREQ=4
*NODE,NSET=BOTTOM
*NODE,NSET=BSLID
*NODE,NSET=TSLID
*NODE,NSET=TOP
*ELEMENT,TYPE=C3D8,ELSET=SOLID
*ELSET,ELSET=ETOP
*ELSET,ELSET=EBOT
*surface,type=node,NAME=ANSET
BSLID,
*surface,NAME=BSURF
ETOP,S1
*CONTACT PAIR,INTERACTION=SLIDE,SMALL SLIDING, TYPE=SURFACE TO SURFACE
ANSET,BSURF
*SURFACE INTERACTION,NAME=SLIDE
*FRICTION
0.,
*SOLID SECTION,ELSET=SOLID,MATERIAL=SOLMAT
*MATERIAL,NAME=SOLMAT
*ELASTIC
30.E6,.0
*BOUNDARY
TOP,1,3
BOTTOM,1,3
**
** step 1: Shrink fit with *CONTACT INTERFERENCE.
** 	   Establish base state.
**
*STEP ,NLGEOM
*STATIC
0.25,1.
*CONTACT INTERFERENCE,SHRINK
ANSET,BSURF
*ENERGY FILE,FREQ=4
*CONTACT PRINT,SLAVE=ANSET,MASTER=BSURF
*CONTACT FILE,SLAVE=ANSET,MASTER=BSURF,F=4
*EL FILE ,FREQ=4
S,
E,
*NODE FILE,FREQ=4
U,
RF,
*ENERGY PRINT
*EL PRINT ,SUM=NO
S,
E,
*NODE PRINT,SUM=NO
RF,
*END STEP
**
** step 2: slide top cube to the right w/o friction
**
*STEP,PERT
*STATIC
*BOUNDARY
TSLID,1,,0.1
TOP,1,,0.1
*ENERGY FILE,FREQ=6
*EL FILE ,FREQ=6
S,
E,
*NODE FILE,FREQ=6
U,
RF,
*CONTACT FILE,SLAVE=ANSET,MASTER=BSURF,F=6
*ENERGY PRINT
*EL PRINT ,SUM=NO
S,
E,
*NODE PRINT,SUM=NO
RF,
*END STEP
**
** step 3: change surface friction
**
*STEP,NLGEOM
*STATIC
1.0,1.0
*CHANGE FRICTION,INTERACTION=SLIDE
*FRICTION
0.3,
*ENDSTEP
**
** step 4: slide to the left w/ friction
**
*STEP,PERT
*STATIC
*BOUNDARY
TSLID,1,,-0.1
TOP,1,,-0.1
*ENERGY FILE,FREQ=6
*EL FILE, FREQ=6
S,
E,
*NODE FILE, FREQ=6
U,
RF,
*CONTACT FILE,SLAVE=ANSET,MASTER=BSURF, FREQ=6
*CONTACT PRINT,SLAVE=ANSET,MASTER=BSURF, FREQ=6
*PRINT,CONTACT=YES
*ENDSTEP