pushover curve

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Paolo
Posts: 12
Joined: Tue Feb 21, 2006 9:01 am
Location: Italy Bologna

pushover curve

Post by Paolo »

Hi everybody!
I’m working on a 3D pushover analysis.
I found that if I build the pushover curve using the roof displacement in x axes and the sum of the base shear in the pillars in y axes, I obtain slightly different results from the ones I obtain using the load factor multiplyed for the sum of the lateral loads in each plane (this difference become much bigger in plastic state).
Is it normal?
What curve should I use?
Thanks a lot.
Good Easter!
silvia
Posts: 3909
Joined: Tue Jan 11, 2005 7:44 am
Location: Degenkolb Engineers
Contact:

Post by silvia »

Paolo,
first of all, go home, it's a holiday weekend, especially in your country!

still,
you should ALWAYS use the node recorder with the reaction.

i wouldn't use anything else, unless I was sure I was doing it perfect.

If you get different results, likely you don't have the y orientation for all your pier elements to be the same. or something else, who knows, right?
the reactions are reactions are reactions. they are in global coordinates, too. so both of these reduce your chances of error, exepct for one thing:
MAKE SURE YOU INCLUDE ALL YOU SUPPORT NODES!!!

happy Easter!
Silvia Mazzoni, PhD
Structural Consultant
Degenkolb Engineers
235 Montgomery Street, Suite 500
San Francisco, CA. 94104
ekalkan
Posts: 15
Joined: Tue Nov 01, 2005 4:19 pm

Post by ekalkan »

Are you sure that you have no movement in the other direction other than the load applied in the pushover
silvia
Posts: 3909
Joined: Tue Jan 11, 2005 7:44 am
Location: Degenkolb Engineers
Contact:

Post by silvia »

it could be, but any loads in that direction would be self equilibrating (sum=0)
Silvia Mazzoni, PhD
Structural Consultant
Degenkolb Engineers
235 Montgomery Street, Suite 500
San Francisco, CA. 94104
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