friction isolator

[Zsediqi]

hello everyone ,
i modeled a base isolated structure in seismostruct .
when i run it i get an error.
the error message is:
definition of element connectivity: element C29_-1: The external (excluding offsets) and internal (including offsets)elements can not be perpendicular . seismostruct can not run the analysis.

i get the same error for another isolator next to that isolator .
How can i solve this problem?

secondly, is it possible to edit the storey heights after creating a model? i could not see anything in the editing module for editing story heights.

[seismosoft]

1. The error message describes correctly the problem. The directions of the internal (without the offsets) and external (with the offsets) element cannot be perpendicular, because this causes problems in the stiffness matrix transformations. Probably, this is a very small element created close to a beam-column joint. Find it and correct the problem manually
2. After the model is created from the Building Modeller and passed to SeismoStruct's main window, you can only change the mode coordinates.
Seismosoft Support

[Zsediqi]

thank you so much for your reply.

[zamani]

Hi,
I modeled a base-isolated structure equipped with FPS isolator as a SDOF system. The FPS isolator is modeled using the link element of “Isoator2”. But SDOF model does not run under earthquake excitation.

[huffte]

I have had good success modeling FPS isolators using the "plst" nonlinear link. It may be worth a shot. It does seem that the element you have been using is specifically for the FPS isolator though. So it would be interesting to try the "plst" link and see if it runs. Then you would perhaps be able to pinpoint the issue. Best of luck.

[zamani]

Tanks your response
Your model (free sample model) was used and it runs. Since the FPS isolator depends on the velocity, the Isolator2 element must be used. When I use Isolator2 element instead of plst element, it does not run.