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Prestressed modal analysis

Submitted by Hamid.antar on

Dear all,

I am trying to perform a prestresssed modal analysis on a beam , but the results are the same as the modal analysis of the beam without the static force.

Idid static analysis with prestress ON ,EXIT solution , reopen solution, then modal analysis with prestress ON.

Please could anyone help me or show me the right way to do prestressed modal analysis .

Regards,

Antar

Antar,

 

Based on your post,  it is difficult to tell whether you have everything set up correctly. Could you post your input file here so that we can dig more.

 

Good luck.

 

Weiming Lan

Sun, 05/17/2009 - 21:56 Permalink

Hi,

 Is it the case that the pre-stress is not having any noticeable effect on the natural frequencies?  It is quite possible in case of stiff members, or if the stresses are not large enough to influence the stiffness of the member.  The word "beam" gives me this feeling, since stress stiffening is significant in thin members, usually.

Regards,

Jayadeep U.B.

Mon, 05/18/2009 - 11:31 Permalink