*HEADING
***************
** BOTTOM LAYER **
***************
*NODE,NSET=SIDES
1,    0.,  -33.33
5,  100.,  -33.33
11,   0.,  -16.66
15, 100.,  -16.66
21,   0.,  -00.00
25, 100.,  -00.00
*NGEN,NSET=BOTTOM
1,5,1
*NGEN,NSET=MID
11,15,1
*NGEN,NSET=TOP
21,25,1
*ELEMENT,TYPE=CPE8R,ELSET=EALL
1, 1,3,23,21,2,13,22,11
2, 3,5,25,23,4,15,24,13
*SOLID SECTION,ELSET=EALL,MATERIAL=ELAS
*MATERIAL,NAME=ELAS
*DENSITY
1., 
*ELASTIC
2.8E7, .2
***INITIAL CONDITIONS,TYPE=STRESS,GEOSTATIC
**EALL, 0.0, 0.0, -833.33, -33.33, 0.3333
**
**
*STEP
*SUBSTRUCTURE GENERATE,TYPE=Z3,OVERWRITE
*RETAINED NODAL DOFS,SORTED=NO
BOTTOM,2
TOP,2
*BOUNDARY
SIDES,1
*SUBSTRUCTURE LOAD CASE,NAME=BOUND
*DLOAD
EALL,GRAV,25., 0.,-1.,0.
*END STEP