Stiffness Degradation

[nimatehran]

Hello,

I want to consider "Stiffness Degradation" in steel material in a steel frame. what type of material should i use?

uniaxialMaterial Pinching4

or

uniaxialMaterial SteelMPF

or
...?
Does anyone have an example?

With Best Regards

[fmk]

both, in theory, will work. you could start iwth the distributed frame example provided at:
http://opensees.berkeley.edu/wiki/index ... ment_Frame

and then replace the stell material used there with the different options.