*HEADING
: SIMPLE CONTACT TEST, SMALL SLIDING, CAX6MH
** Contact Features Tested:
**	*CONTACT INTERFERENCE, *FRICTION, *CHANGE FRICTION (mu=0 and mu=0.3)
** SLIDING STEPS ARE PERTURBATION STEPS
*RESTART,WRITE, FREQ=4
*NODE
1,1.,5.
3,2.,5.
9,2.,10.
7,1.,10.
5,1.5,7.5
11,1.,9.9
13,2.,9.9
15,1.5,12.4
19,2.,14.9
17,1.,14.9
*NGEN
1,3
3,9,3
7,9
1,7,3
11,13
13,19,3
17,19
11,17,3
*ELEMENT,TYPE=CAX6MH,ELSET=BOTEL
1,1,3,7,2,5,4
2,3,9,7,6,8,5
*ELEMENT,TYPE=CAX6MH,ELSET=TOPEL
3,11,13,17,12,15,14
4,13,19,17,16,18,15
*ELSET,ELSET=SOLID
BOTEL,TOPEL
*SOLID SECTION,ELSET=SOLID,MATERIAL=SOLMAT
*MATERIAL,NAME=SOLMAT
*ELASTIC
30.E6,0.
*SURFACE INTERACTION,NAME=SLIDE
1.,
*FRICTION
0.,
*surface,NAME=BOTS
2,S2
*surface,NAME=TOPS
3,S1
*CONTACT PAIR,INTERACTION=SLIDE, SMALL SLIDING, TYPE=SURFACE TO SURFACE
BOTS,TOPS
*BOUNDARY
1,1,2,0.
2,1,2,0.
3,1,2,0.
17,1,2,0.
18,1,2,0.
19,1,2,0.
**
** step 1: Shrink fit with *CONTACT INTERFERENCE.
** 	   Establish base state.
*STEP,INC=20,NLGEOM
*STATIC
0.2,1.,0.2,0.2
*CONTACT INTERFERENCE,SHRINK
BOTS,TOPS
*OUTPUT,FIELD
*ELEMENT OUTPUT
S,
*OUTPUT,FIELD
*NODE OUTPUT
U,
*OUTPUT,FIELD
*CONTACT OUTPUT,VARIABLE=PRESELECT,SLAVE=BOTS,MASTER=TOPS
*CONTACT PRINT,SLAVE=BOTS,MASTER=TOPS
*PRINT,CONTACT=YES
*ENDSTEP
**
** step 2: slide radially out w/o friction, linear perturbation
**	   with shrink-fit base state.
**
*STEP,PERT,NLGEOM
*STATIC
1.0,1.0
*BOUNDARY,OP=MOD
17,1,,0.1
18,1,,0.1
19,1,,0.1
11,1,,0.1
12,1,,0.1
13,1,,0.1
14,1,,0.1
15,1,,0.1
16,1,,0.1
*OUTPUT,FIELD
*ELEMENT OUTPUT
S,
*OUTPUT,FIELD
*NODE OUTPUT
U,
*OUTPUT,FIELD
*CONTACT OUTPUT,VARIABLE=PRESELECT,SLAVE=BOTS,MASTER=TOPS
*CONTACT PRINT,SLAVE=BOTS,MASTER=TOPS
*PRINT,CONTACT=YES
*ENDSTEP
**
** step 3: change surface friction
**
*STEP
*STATIC
1.0,1.0
*CHANGE FRICTION,INTERACTION=SLIDE
*FRICTION
0.3,
*ENDSTEP
**
** step 4: slide radially in w/ friction, linear perturbation
** 	   with shrink-fit base state.
**
*STEP,NLGEOM,PERT
*STATIC
*BOUNDARY
17,1,,-0.1
18,1,,-0.1
19,1,,-0.1
11,1,,-0.1
12,1,,-0.1
13,1,,-0.1
14,1,,-0.1
15,1,,-0.1
16,1,,-0.1
*OUTPUT,FIELD
*ELEMENT OUTPUT
S,
*OUTPUT,FIELD
*NODE OUTPUT
U,
*OUTPUT,FIELD
*CONTACT OUTPUT,VARIABLE=PRESELECT,SLAVE=BOTS,MASTER=TOPS
*CONTACT PRINT,SLAVE=BOTS,MASTER=TOPS
*PRINT,CONTACT=YES
*ENDSTEP