Hello every one

I am trying to accomplish nonlinear time history analysis using CSI Bridge with concentrated plastic hinge model. My plastic hinge model is modified Takeda. The problem I have is related to modeling unloading section of moment-curvature diagram in which it must have stiffness degrading (i.e. Alpha is 0.5). Beside that, I don't know that why the output of the CSI Bridge for a non-degraded state (Alpha is 0.0) is as follows .

I would appreciate if anyone help me with these two problems.