Push-Over Analysis

[peyman1358]

Hi all

I have a bridge model.
To push over analysis, I use the OpenSees example file for push over analysis. In these example you define Dmax (maximum displacement of pushover) as a factor of column length (0.1*Lcol).
When I use low Dmax (less than 0.5*L) I have good result, the program does not transfer to the par of "if analysis fail...", but if I increase my Dmax, so I have more push and program use othe stuff such as "Newton with Intial Tangent...". The result of my push over seems normally, but my structure should die in big push (Dmax=2.0*Lcol), but the push over diagram still continue and it can reach load factor of 4.
Rnning Open Sees trying othe approach such as Newton with intial tangent statrs frm load factor=1.57, I think from this step the bridge should die and I should have negative slpe in my diagram, but as i explained my strucutre still continue till large load factor.
Can you guide what is the problem in my model?

Thanks
Peyman

[silvia]

opensees goes on until it runs into serious problems.
look at your pushover curve, you may have lost significant stregnth.
also, if you use materials such as stee02, it will control the results.

[mehdi1995]

hi payman
I have the same problem as you mentioned!as i increase the analysis steps the pushover curve just increases and it seems that it wont come down!! did you manage to fix it?
i tryed the steel02 material but it wont converge even in gravity analysis!