*HEADING
**
** Contact between aligned blocks in 3D.
**
*NODE,NSET=NB1
1, 0.,0.,0.
2, 1.,0.,0.
3, 2.,0.,0.
4, 3.,0.,0.
5, 4.,0.,0.
11,0.,1.,0.
12,1.,1.,0.
13,2.,1.,0.
14,3.,1.,0.
15,4.,1.,0.
21,0.,0.,1.
22,1.,0.,1.
23,2.,0.,1.
24,3.,0.,1.
25,4.,0.,1.
31,0.,1.,1.
32,1.,1.,1.
33,2.,1.,1.
34,3.,1.,1.
35,4.,1.,1.
*ELEMENT,ELSET=EB1,TYPE=C3D8R
1,1,2,12,11,21,22,32,31
*ELGEN,ELSET=EB1
1,4,1,1
*NSET,NSET=FIX_N
1,2,3,4,5,21,22,23,24,25
*BOUNDARY
FIX_N,2,2
1,1,3
5,2,3
**
*NODE,NSET=NB2
101,0.,1.1,0.
102,1.,1.1,0.
103,2.,1.1,0.
104,3.,1.1,0.
105,4.,1.1,0.
111,0.,2.1,0.
112,1.,2.1,0.
113,2.,2.1,0.
114,3.,2.1,0.
115,4.,2.1,0.
121,0.,1.1,1.
122,1.,1.1,1.
123,2.,1.1,1.
124,3.,1.1,1.
125,4.,1.1,1.
131,0.,2.1,1.
132,1.,2.1,1.
133,2.,2.1,1.
134,3.,2.1,1.
135,4.,2.1,1.
*ELEMENT,ELSET=EB2,TYPE=C3D8R
101,101,102,112,111,121,122,132,131
*ELGEN,ELSET=EB2
101,4,1,1
*NSET,NSET=LOAD_N
111,112,113,114,115,131,132,133,134,135
**
*ELSET,ELSET=EALL
EB1,EB2
**
*SOLID SECTION,ELSET=EALL,MATERIAL=MAT1
*MATERIAL,NAME=MAT1
*ELASTIC
1.E6,0.2
*DENSITY
1., 
*SURFACE,TYPE=ELEMENT,NAME=SB1
EB1,
*SURFACE,TYPE=ELEMENT,NAME=SB2
EB2,
**
*AMPLITUDE,NAME=SMOOTH,DEFINITION=SMOOTH STEP
0.,0.,1.E-3,-0.1,5.E-3,1.
**
*NSET, NSET=QA_TEST_ALLNODES
NB1, NB2
**
*STEP
*DYNAMIC,EXPLICIT,DIRECT
3.16e-4,5.E-3
**
*BOUNDARY,AMPLITUDE=SMOOTH
LOAD_N,2,2,0.001
**
*CONTACT PAIR,INTERACTION=LINEAR, MECHANICAL CONSTRAINT=PENALTY,WEIGHT=1.0
SB1,SB2
*SURFACE INTERACTION,NAME=LINEAR,PADTHICKNESS=0.1
*CONTACT DAMPING,DEFINITION=CRITICAL DAMPING FRACTION
0.,
*SURFACE BEHAVIOR,NO SEPARATION,PRESSURE-OVERCLOSURE=LINEAR
1.E6,
**Pressure-overclosure slope = E_interface / t_interface
*FRICTION,ROUGH,SHEAR TRACTION SLOPE=416666.7
**Shear traction slope = G_interface / t_interface
**                     = E_int / t_interface / (2*(1+nu_interface))
**
*FILE OUTPUT,NUM=1
*NODE FILE
U,
**
*OUTPUT, FIELD, NUMBER INTERVAL=1
*NODE OUTPUT, NSET=QA_TEST_ALLNODES
U,
*OUTPUT,FIELD,VARIABLE=PRESELECT
*OUTPUT,HISTORY,VARIABLE=PRESELECT,TIMEINT=0.005
*END STEP