*HEADING
Link modeled with B31 beam elements
**  ----------------------------------------------
**
**               NODE DEFINITION
**
*NODE, nset=nall
**
         1,0.000000000E+00,0.000000000E+00,0.000000000E+00
         2,5.000000000E-02,0.000000000E+00,0.000000000E+00
         3,1.000000000E-01,0.000000000E+00,0.000000000E+00
         4,1.500000000E-01,0.000000000E+00,0.000000000E+00
         5,2.000000000E-01,0.000000000E+00,0.000000000E+00
         6,2.500000000E-01,0.000000000E+00,0.000000000E+00
         7,3.000000000E-01,0.000000000E+00,0.000000000E+00
         8,3.500000000E-01,0.000000000E+00,0.000000000E+00
         9,4.000000000E-01,0.000000000E+00,0.000000000E+00
        10,4.500000000E-01,0.000000000E+00,0.000000000E+00
        11,5.000000000E-01,0.000000000E+00,0.000000000E+00
**
**  ----------------------------------------------
**
**               ELEMENT DEFINITION
**
*ELEMENT,TYPE=B31
         1,1,2
         2,2,3
         3,3,4
         4,4,5
         5,5,6
         6,6,7
         7,7,8
         8,8,9
         9,9,10
        10,10,11
**
**  ----------------------------------------------
**
**               ELEMENT PROPERTY DEFINITION
**
*ELSET,ELSET=PROP1
1,2,3,4,5,6,7,8,9,10
**
*BEAM SECTION,ELSET=PROP1,SECTION=RECT,MATERIAL=STEEL,TEMP=GRAD
3.000E-02,1.000E-02
0.000E+00,0.000E+00,-1.000E+00
,
**
**  ----------------------------------------------
**
**               MATERIAL DEFINITION
**
*MATERIAL,NAME=STEEL
*ELASTIC
 2.069999944E+11, 3.000000119E-01,
*DENSITY
 7.800000000E+03,
**
*NSET,NSET=RETNODES
1, 11
**
**  ----------------------------------------------
**
*STEP
*FREQUENCY,EIGENSOLVER=LANCZOS
20,
*BOUNDARY
RETNODES, 1,6
*END STEP
**
**  ----------------------------------------------
**
**               SUBSTRUCTURE GENERATION
**
*STEP
*SUBSTRUCTURE GENERATE, TYPE=Z1, RECOVERY MATRIX=YES, 
 MASS MATRIX=YES, OVERWRITE
*FLEXIBLE BODY, TYPE=ADAMS
*RETAINED NODAL DOFS
RETNODES, 1,6 
*SELECT EIGENMODES,generate
1,20
*END STEP