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Message 1 of 2
pevelor
480 Views, 1 Reply

Modal analysis

Hi

 

I am performing seismic analysis. After running modal analysis to find a how many modes to use I only get mass participation up to 55 using 60 modes.

 

During calculations, I receive a warning regarding eigenvalues. Is this effecting load to mass conversion?

 

All supports are defined as elastic.

 

Please help me solve this. I want mass participation over 90%.

 

Regards Peder

Load_to_Mass_Conversion.png

Modal_Analysis_Parameters.pngTable_modal_analysis.png

1 REPLY 1
Message 2 of 2
Artur.Kosakowski
in reply to: pevelor

Try to increase the number of modes. You may also try to use the pseudo modes approach.

 

IMHO if the warning is about missing modes then for seismic analysis then you can ignore it as your goal is mass participation rather than exact values of eigenfrequencies.

 

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

 

 



Artur Kosakowski

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