convert combs to nonlinear cases or use combs of individual nonlinear cases?

[structuralbug]

Dear all, I'm looking at modelling a cable stayed bridge in SAP2000, one of the issues seems unclear to me is about creating the nonlinear loadcases. I'm thinking to make individual nonlinear cases first (i.e. dead&prestress, wind, thermal, traffic etc.), then to make combinations of them, rather than what I did before to make combinations first then convert them to nonlinear cases. This was a consideration to use the load envlopes later. I am puzzled by the differences between this two approaches and their impact to the results,can anyone please advise me? Thanks.

 

[Guest262653]

If you are interested in non linear behaviour you can't just add individual non linear load cases. It makes no sense as the individual effects are non superimposable. You must perform a non linear analysis for each load combination.