getLoadFactor signs

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kavian
Posts: 7
Joined: Tue Aug 13, 2013 6:11 pm
Location: Universidad de Chile

getLoadFactor signs

Post by kavian » Sun Apr 18, 2021 7:41 pm

Hey,

Some months ago (before last update) I was able to get negative outputs from this command, but now it just prints positive values and no negatives... All negatives values are now "0".

This happened when applying a cyclic loading to elements (truss, fbc, etc) to calibrate buckling. Now I cant plot pushover curves the way I did :-)

Any idea what could have change?

Thank you!
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mhscott
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Location: Corvallis, Oregon USA
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Re: getLoadFactor signs

Post by mhscott » Sun Apr 18, 2021 8:41 pm

Can you provide a minimum working example showing the issue? Thanks!

kavian
Posts: 7
Joined: Tue Aug 13, 2013 6:11 pm
Location: Universidad de Chile

Re: getLoadFactor signs

Post by kavian » Mon Apr 19, 2021 7:11 am

mhscott wrote:
Sun Apr 18, 2021 8:41 pm
Can you provide a minimum working example showing the issue? Thanks!
Good Morning Prof.

Attached is a simplified example, everything works fine in tension (where the loads have the same sign of the displacement) but when the loads should became negative, the load factor goes to "0".

I was able to show the compressive portion of the curve when I use a negative load for the negative displacement, but in that case, like a mirror of the previous case, the positive values of the loads give me a loadfactor of "0".

This is an older version of what I do now but none of them works now :(

edit: maybe my problem is not about the loadfactor command itself. I replaced it with nodal reactions to see the actual loads and for some reason the same happens. I tested with elastic beam-column as well. The same.
Thank you in advance!

ps. I realized files cannot be attached. Files are stored at this Link .
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kavian
Posts: 7
Joined: Tue Aug 13, 2013 6:11 pm
Location: Universidad de Chile

Re: getLoadFactor signs

Post by kavian » Mon Apr 19, 2021 8:20 am

Haha, got the solution.

Updated OpenseesPy from 3.2.2.9 to 3.2.2.10 and everything goes fine again :-)
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