Number of modes of 3D model
Number of modes of 3D model
(OP)
Hi,
I am performing a model analysis using eigenvectors.
I have a 3D structure that has all translational and rotational dof's active which requires over 90 modes to obtain a mass participation ratio of 90% in all translational directions. The structure is inclined, which means that non-lateral movement has UX and UZ components, which slows down the process of obtaining a satisfactory mass participation ratio. Further, I have many modes in a row which contribute with practically zero to the response because only a very small part of the structure is moving.
Does anyone know a trick to eliminate these insignificant modes from the eigen modal analysis? I see that advanced load parameters can be specified but I don't know if this might help me somehow..
Thanks :)
I am performing a model analysis using eigenvectors.
I have a 3D structure that has all translational and rotational dof's active which requires over 90 modes to obtain a mass participation ratio of 90% in all translational directions. The structure is inclined, which means that non-lateral movement has UX and UZ components, which slows down the process of obtaining a satisfactory mass participation ratio. Further, I have many modes in a row which contribute with practically zero to the response because only a very small part of the structure is moving.
Does anyone know a trick to eliminate these insignificant modes from the eigen modal analysis? I see that advanced load parameters can be specified but I don't know if this might help me somehow..
Thanks :)





RE: Number of modes of 3D model
RE: Number of modes of 3D model
Check the following link for reference:
https://wiki.csiamerica.com/display/kb/Ritz+vs.+Ei...
and the following eng-tips discussion:
http://www.eng-tips.com/viewthread.cfm?qid=239542
RE: Number of modes of 3D model
Analysis and Design of arbitrary cross sections
Reinforcement design to all major codes
Moment Curvature analysis
http://www.engissol.com/cross-section-analysis-des...