I'm working one my first fullsize project in RSAP(Robot Structural Analysis Proffesional) 2011. I have finished the model but, meshing and vertification goes smooth but here is also were the first problems occur. The differences in the stiffness of the materials and of course eccentric arcitchture makes the modal analysis though. The model doesn't reach 90% participation of mass for each of the horizontal direction before after 300 modes.
Any advise would be highly appreciated.