Which material to use

[OmarA]

Hello everyone,

I am trying to model connections in my model (15 story steel building using concentrated plasticity for the beams and fibre section for the columns) using Two Node Link Element. I will be using this model for IDA. I would appreciate if anyone could advice me which material to use for the following:

1. The axial behaviour of the connections is similar to ElasticPP material (used as force-deformation) but the stiffness (slope) in the tension is different from the compression. Which material can I use? P.S - I want the cyclic behaviour of ElasticPP.

2. The failure deformation in tension is 0.2 but for compression it's 2, since the compression failure depends on the column capacity. So, the connection can fail in tension but still work in compression. How can I do that in opensees?

3. My model is complicated. Is it advised to use MinMax material in general or it can cause numerical problems?

Thanks in advance