nonlinear elements

[sgs]

Hi all,
My model is a 2span steel frame (with bilinear material, steel01 and fiber sections).
When I run it , opensees will be suddenly closed and I can not figure out what is the problem.
When I run it with only one nodes in the middle of the column and beam parts, it will finish the analysis without any errors.(I had to make dt very small to get the convergence!)
Do you have any idea?

[vesna]

For the information you provided I can not know what is causing the program to close suddenly. It happens if OpenSees encounters line that it can not read. Probably, there is an error somewhere in your code.