*HEADING
 : Adjust contact surface normal at symmetry plane
 Finite sliding example with CPE8 elements
 Local cylidrical coordinate system
*SYSTEM
 0.0, 0.0, 0.0, 2., 1., 0.
*NODE, NSET=NALL
   1,  0.0,  1.5, 0.0
   9,  1.5,  0.0, 0.0
  11,  0.0,  1.75,0.0
  19,  1.75, 0.0, 0.0
  21,  0.0,  2.0, 0.0
  29,  2.0,  0.0, 0.0
  31,  0.0,  2.25,0.0
  39,  2.25, 0.0, 0.0 
  41,  0.0,  2.5, 0.0
  49,  2.5,  0.0, 0.0
 101,  0.0,  2.6, 0.0
 109,  2.6,  0.0, 0.0
 111,  0.0,  2.8, 0.0
 119,  2.8,  0.0, 0.0
 121,  0.0,  3.0, 0.0
 129,  3.0,  0.0, 0.0
 131,  0.0,  3.25,0.0
 139,  3.25, 0.0, 0.0
 141,  0.0,  3.5, 0.0
 149,  3.5,  0.0, 0.0
  99,  0.0, 0.0, 0.0
*NGEN, LINE=C, NSET=NALL
   1,  9, 1, 99
  11, 19, 1, 99
  21, 29, 1, 99
  31, 39, 1, 99
  41, 49, 1, 99
 101,109, 1, 99
 111,119, 1, 99
 121,129, 1, 99
 131,139, 1, 99
 141,149, 1, 99
*ELEMENT,TYPE=CPE8
  1,  1,  3, 23, 21,  2, 13, 22, 11
 11,101,103,123,121,102,113,122,111
*ELGEN,ELSET=EALL
  1, 4,2,1,2,20,4
 11,4,2,1,2,20,4
*solid section,elset=EALL,mat=MAT1
*MATERIAL,NAME=MAT1
*ELASTIC
 3000.0,0.2
*ELSET,ELSET=EIN
 5,6,7,8
*ELSET,ELSET=EOUT
 11,12,13,14
*surface, NAME=MASTER, TRIM=YES
 EIN,
*surface, NAME=SLAVE
 EOUT,
*CONTACT PAIR,INTERACTION=NONE
 SLAVE,MASTER
*SURFACE INTERACTION,NAME=NONE
*NSET, NSET=NXSYMM
 1, 11, 21, 31, 41, 101, 111, 121, 131, 141
*NSET, NSET=NYSYMM
 9, 19, 29, 39, 49, 109, 119, 129, 139, 149
*TRANSFORM, NSET=NALL, TYPE=C
 0.,0.,0., 0., 0., 1.
**
** STEP 1 : Apply pressure load
**
*STEP, NLGEOM, INC=50
*STATIC
 ,1.0
*DLOAD
 15, P3, 100.0
 16, P3, 100.0
 17, P3, 100.0
 18, P3, 100.0
*BOUNDARY
 NXSYMM, YSYMM
 NYSYMM, YSYMM
*PRINT, CONTACT=YES
*NODE PRINT, F=0
*EL PRINT, F=0
*CONTACT PRINT, FREQ=100
*CONTACT FILE, MASTER=MASTER, SLAVE=SLAVE, FREQ=100
 CSTRESS, CDISP,
*END STEP
**
** STEP 2 : Remove pressure load
**
*STEP, NLGEOM, INC=50
*STATIC
 ,1.0
*DLOAD, OP=NEW
 15, P3, 0.0
 16, P3, 0.0
 17, P3, 0.0
 18, P3, 0.0
*PRINT, CONTACT=YES
*NODE PRINT, F=0
*EL PRINT, F=0
*CONTACT PRINT, FREQ=100
*CONTACT FILE, MASTER=MASTER, SLAVE=SLAVE, FREQ=100
 CSTRESS, CDISP,
*END STEP