Questions:

The pushover analysis stops since the Maximum displacement reaches the user-defined maximum value = 100inch.



However, this joint is attached to a member that is assigned to GRPELA and GRPSEG in the collapse input file.

The member was also assigned MEMELA and MEMSEG, according to Section 4.5 of the Collapse Advanced Manual.

Is there an available approach to prevent the joint from causing the analysis to converge before the primary plastic elements?

Answers:

SACS Collapse programs don't have a feature to exclude a joint from the maximum deflection check. We understand the need to set secondary members to elastic, but with 100 inches of deflection, those members become plastic under the current loading.

If you want to exclude those parts from the analysis, we have the following suggestions:

1. Convert the secondary components into dummy structures (non-structural models). This approach allows loads to remain on the structures while removing them from the model during the collapse analysis.

2. Convert the secondary components into a superelement. This modification allows their loads and linear stiffness to be applied to the structure during the collapse analysis while the related joints are already removed from the model.

3. You can increase the maximum deflection on the CLPOPT line and then manually check the deflection of all joints. However, as mentioned above, 100-inches deflection means those topside elements may already become plastic, and the linear elastic assumption may not be accurate.