/PREP7

FINISH
/SOLU
ANTYPE,STATIC          ! Static analysis
NLGEOM,ON              ! Large deflection analysis
PSTRES,ON              ! Flag to calculate the prestress matrix

SOLVE
FINISH


!
! Prestressed modal analysis
!

/SOLU
ANTYPE,MODAL       ! Modal analysis
nmodes = 3	     ! Anzahl der Moden, die angezeigt werden sollen
UPCOORD,1.0,ON     ! Display mode shapes relative to deformed geometry 
                   !   in the postprocessor.
PSTRES,ON          ! Prestress effects ON
MODOPT,lanb,nmodes ! Select eigensolver
MXPAND,nmodes,3        ! Specify the number of modes to expand, if desired.
PSOLVE,EIGLANB     ! Calculate the eigenvalues and eigenvectors.
                   !  Use EIGLANB or EIGFULL to match MODOPT command.
EXPASS,ON
PSOLVE,EIGEXP      ! Expand the eigenvector solution. (Required if you
                   !   want to review mode shapes in the postprocessor.)
FINISH

/solu