Hinge and PMM in SAP 2000 V12 Pushover Analysis

[philipckwusa]

Hi,
I am doing pushover for a bridge bent. However, SAP V12 gave me error messages. For P-M3 input, I used the prestress pile IA from (Concrete Technology Corporation) CTC and modifed to SAP input as ratio;however, I got "The axial force is not increasing monotonically at point 11 on curve 1. Some people use PMM but since this is 2D pushover, I don't think PMM is needed.
Besides, it also said curve must be convex. I want to use the infromation from CTC and do not want to adjust.
Is there away to do it in SAP?

Thank!!

 

[stressed]

Could you elaborate more on what you did for input to define the hinge? Because there is no ratio input for hinges in SAP2000.

SAP offers three types of hinges: FEMA and Caltrans hinge options which you can assign without defining anything beforehand, or the fiber P-M-M hinge which you need to define before assigning. If you're trying to match SAP results with another program, obviously you need to make sure you're comparing apples to apples with how the programs handle plastic hinges.