Assembled stiffness matrix and the section failure

[baijiulin]

Hello all.
Can we extract the assembled stiffness matrix of the model when we do ststic pushover analysis? If can,how to make it in each step in pushover analysis?

Also,can you give me some idea or suggestions on how to define a section(beams and column) failure? If we have the definition of section failure,and one end of a unit have failed,how to consider the failure end and the other end which can withstand load? wo will get the failure path when the structure fail,according to the way.

Thank you all of you giving me inspiration! wait...