*heading
pressdepper3d.inp
*preprint,model=yes,contact=yes,history=yes
*node, nset=all
1,1.,0.,0.
2,1.,1.,0.
3,0.,1.,0.
4,0.,0.,0.
5,1.,0.,1.
6,1.,1.,1.
7,0.,1.,1.
8,0.,0.,1.
11,3. ,-1.,-1.1
12,3. ,2. ,-1.1
13,-1.,2. ,-1.1
14,-1.,-1.,-1.1
15,3. ,-1.,-0.1
16,3. ,2. ,-0.1
17,-1.,2. ,-0.1
18,-1.,-1.,-0.1
*element, type=c3d8,elset=eall
1, 1,2,3,4,5,6,7,8
2, 11,12,13,14,15,16,17,18
*solid section,material=mat1,elset=eall
1.,
*material,name=mat1
*density
7800.
*elastic
2.e11,0.3
*surface, name=surf1, type=element
1, s1
*surface, name=surf2, type=element
2, s2
*contact pair,interaction=inter
surf1, surf2
*surface interaction, name=inter
1.
*friction
0.1,
*boundary
5, 2,2
8, 1,2
5, 3,3,0.
6, 3,3,0.
7, 3,3,0.
8, 3,3,0.
11, 1,3
12, 1,3
13, 1,3
14, 1,3
**
** step 1, natural eigenpairs; no prestress
*step,name=frequency1
*frequency,eigensolver=lanczos
12,
*end step
**
** step 2
*step,name=general1
*static
1.,1.
*boundary
5, 3,3,-0.2
6, 3,3,-0.2
7, 3,3,-0.2
8, 3,3,-0.2
*print,solve=no
*output,history,freq=0
*output,field
*node output
u,
*contact output
cstress,
*node print
u,
*el print
s,
*contact print
*output,history,freq=0
*output,field,variable=preselect
*node output
u,
*contact output
cstress,cdisp
*end step
**
** step 3
*step,name=frequency2
** preloaded; reference eigenpairs; eigenvalues should be higher than for step 1
*frequency,eigensolver=subspace
12,
*end step
**
** step 4
*step,name=frequency3
*frequency,eigensolver=subspace
12,
** eigenvalues should be less than for step 3
*contact controls,pressure dependent perturbation=1.e12,slave=surf1,master=surf2
0.
*end step
**
** step 5
*step,name=frequency4
*frequency,eigensolver=subspace
12,
** The elopw printed contact stiffness should be 10 times smaller than for step 4
** spectrum should be less than of step 4
*contact controls,pressure dependent perturbation=1.e13
0.
*end step
** step 6
*step,name=frequency5
*frequency,eigensolver=lanczos
12,
** spectrum should be the same as of step 4
*contact controls,pressure dependent perturbation=1.e12
0.
*end step
**
** step 7
*step,name=general2
*static
1.,1.
*boundary
5, 3,3,-0.3
6, 3,3,-0.3
7, 3,3,-0.3
8, 3,3,-0.3
*end step
**
** step 8
*step,name=frequency6
*frequency,eigensolver=lanczos
12,
** spectrum should differ from step 3.
*contact controls,pressure dependent perturbation=0.,slave=surf1,master=surf2
0.
*end step
**
** step 9
*step,name=frequency7
** spectrum should be the same as for step 8.
*frequency,eigensolver=subspace
12,
*end step
**
** step 10
*step,name=frequency8
*frequency,eigensolver=lanczos
12,
** Remove all contact constraints; spectrum should be
** the same as for step 1 (nlgeom=no in effect).
*contact controls,pressure dependent perturbation=1.e15
*end step