*Heading
 B21 Elements, Static Analysis
*Node
*Element, type=B21
*Elset, elset=I1, generate
*Beam Section, elset=I1, Section=RECT,material=Elas
1, 1
0.,0.,-1.
*Material, name=Elas
*Density
10.,
*Elastic
 1e+08,0.
*step
*frequency,eigen=lanc
24,
*boundary
1,1,6
2,1,6
3,1,6
*end step
*STEP
*substructure generate, type=z1, overwrite,
recovery matrix=yes, mass matrix=yes,
libr=lib_smdef_beam2D
*RETAINED NODAL DOFS,sorted=no
*Retained Eigenmodes,generate
*substructure matrix output, stiffness=yes,
mass=yes, recovery=yes, file=lib_smdef_beam2D
*END STEP