Pinching4 Material parameters

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javid
Posts: 8
Joined: Sun May 12, 2013 8:36 pm

Pinching4 Material parameters

Post by javid »

Dear All,
I try modeling a beam-column joint that contains pinching4 material,
I want to know how to define the value of p1( Positive/Negative envelope Stress).
Regards
Javid
fbeckwit
Posts: 26
Joined: Wed May 15, 2013 3:23 pm
Location: University of California, San Diego

Re: Pinching4 Material parameters

Post by fbeckwit »

As I understand the material, you define the stress envelope manually by selecting the points of the force-displacement relationship. The model then constructs the backbone curve by linear interpolation between those points.

ePd1 ePd2 ePd3 ePd4 <-- Displacement points of backbone curve;
ePf1 ePf2 ePf3 ePf4 <-- Force points of backbone curve;

(ePd#,epf#) would then represent a point. The backbone curve for the negative stress envelope is defined in the same manner (substitute a N for P in the variables above) or they can be omitted entirely and the material will assume they are the same as the points for the positive backbone curve with opposite sign value.

Hope this helps.
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