Incremental Dynamic Analysis

[ruipinho]

Dear Zsediqi,

If you are already modelling the isolators through a nonlinear constitutive model, which I suspect you are, given that it is the default option in SeismoStruct, then you do not need to add any additional equivalent viscous damping, given that the "damping effect" of the isolators is already captured by their nonlinear hysteretic relationship.

In other words, the suggestion of your supervisor to use 2% equivalent viscous damping seems very reasonable to me, and if some of your analyses are not converging, increasing the equivalent viscous damping is not necessarily the solution - there might be a myriad of other reasons why the analyses are not converging, as extensively discussed in this Forum and in other Seismosoft technical support channels and material.

Regards,

Rui