Time History analysis for seismic building design

[bastieng]

I'm doing a Time History analysis (sol 109) of a building on seismic isolator in Femap.

As I don't want my calculation time to explode, i have to go for simple way of taking into accont the seimic isolators; they are about 200 of them on the building I want to design.

At the moment I put an horizontal damper and an horizontal spring at each node where i have a seismic isolator.

Does anybody have history whith this kind of analysis?

I want to go a bit further and to have in my model pendulum seismic isolator (spherical bearing); doing a rigid bar to make the pendulum, no problem, but taking into account the friction that occure in this type of system without having a contact is a bit of an issue. Any thought?

Thanks in advance for your comments,
Regards
Bastien