Hi all,
I am running a pushover analysis on a basic cantilever column. If i perform an eigen analysis at first, I got a period of 0.86s; if I perform it after the pushover, the period increase (3s); but if I run the pushover with just 1 step and 0.0001 disp increment, and then I run the eigen, the period is still very high (1.26s). It is supposed to be 0.86 like the fist case!
I have noticed this problem with concrete01 and concrete02 materials; but if I put steel01 instead, it works (0.86s)!!
Can someone explain me why this happens ?? thank you
Eigen after Pushover. Problems with periods
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riccardonitiffi
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selimgunay
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Re: Eigen after Pushover. Problems with periods
If you don't have any axial force, concrete01 does not have any tensile resistance so the moment of inertia can reduce a lot in the first step. That can be the reason