As I have mentioned, recently a new element "element ModElasticBeam2d " has been added to OpenSees framework. However, in the explanation of this element, it is noted that this element is for modeling an elastic one with two springs at the ends. The question is: How should this element incorporate nonlinear behavior? Is this element solely for the elastic part while the two (or one) end springs should be separately modeled as zero-length elements?
Thank you very much for your concern