*heading
	cylindrical membrane
        tested with def-vs-rigid finite sliding contact
*preprint,model=yes,history=yes
*node,nset=nbot
1,1.,0.,0.
2,0.707106781,0.707106781,0.
3,0.,1.,0.
4,-0.707106781,0.707106781,0.
5,-1.,0.,0.
6,-0.707106781,-0.707106781,0.
7,0.,-1.,0.
8,0.707106781,-0.707106781,0.
**
*node,nset=ntop
11,1.,0.,1.
21,0.707106781,0.707106781,1.
31,0.,1.,1.
41,-0.707106781,0.707106781,1.
51,-1.,0.,1.
61,-0.707106781,-0.707106781,1.
71,0.,-1.,1.
81,0.707106781,-0.707106781,1.
*node
1000, 0,0,0
**
*element,type=mcl6,elset=eall
1,1,11,31,3,21,2
2,3,31,51,5,41,4
3,5,51,71,7,61,6
4,7,71,11,1,81,8
*membrane section,elset=eall,material=mone
0.05
*material,name=mone
*elastic
30.e6,0.3
**
** contact definition
**
*surface,name=asurf
eall,spos
*surface,name=rsurf,type=revolution
0.,0.,0.,0.,0.,1.
start, 1.2,  3.0
line,  1.2, -2.0
*rigid body,analytical surface=rsurf,ref node=1000
*contact pair,interaction=rough
asurf,rsurf
*surface interaction,name=rough
**
** history definition
**
**
** Step 1: establish contact
**
*step
*static
0.1,1.
*boundary
1, 2,2,0.0
nbot,3,3,0.0
1000,1,6,0.0
*contact interference,shrink
asurf, rsurf
*el print
s,
e,
*contact print
*controls,parameter=field
1.0e-6,
*print,contact=yes
*output, field, freq=6
*element output, elset=eall
s
*node output
u
*contact output, slave=asurf, variable=preselect
*end step
**
** step 2: change surface friction
**
*step, nlgeom
*static
1.0,1.0
*change friction, interaction=rough
*friction
0.3,
*end step
**
** step 3: slide rigid surface to initiate sliding
**
*step, nlgeom, unsymm=yes
*static
0.1, 1.0
*boundary, op=new
1, 2,2,0.0
nbot,3,3,0.0
1000, 1, 2, 0.0
1000, 4, 6, 0.0
1000, 3, 3, 1.0
*end step