About numIntgrPts for Force-based beamcolumn element

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wooj
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About numIntgrPts for Force-based beamcolumn element

Post by wooj »

Hello
I am peforming IDA with RC frame modeled with Force-based beamcolumn element(5 numIntgrPts).

I am wondering if this points is 2 when the RC frame is on plastic stage, do you think it is wrong modeling?
Responses when 2 and 5 IntgrPts are quite diffrent. Is it related to the accuracy for the plastic stage?
I already referred the technical paper(2011) by Prof. Scott but i can't find the answer.
mhscott
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Re: About numIntgrPts for Force-based beamcolumn element

Post by mhscott »

With force-based elements, you need at least three Lobatto points. With two, you do not get the correct linear solution, which is probably why your results are off, I'm guessing the initial stiffnesses are quite different.
wooj
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Re: About numIntgrPts for Force-based beamcolumn element

Post by wooj »

Thank you for you reply.
WilsonAlarcon
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Re: About numIntgrPts for Force-based beamcolumn element

Post by WilsonAlarcon »

Las carrgas distribuidas intervienen en la rigidéz?
mhscott
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Re: About numIntgrPts for Force-based beamcolumn element

Post by mhscott »

Yes, the distributed loads enter the section state determination, in turn affecting the stiffness.
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