Earthquake Analysis with RSA_Seismic Force


I have a question about Earthquake Analysis with RSA in software.

Why seismic force for both directions (X and Y) has the same value?
In my example construction has very different stiffness in X and Y directions, and I think for that construction, forces may be different, not equal.

Also in your example for RSA, construction has a different frequency (thus and stiffness) in X and Y directions, but the same forces.

Thank you very much for your answer.

Kind regards,

Hello Stefan

Could you please clarify which RSA example you are referring to?
And can you tell us the forces you are comparing?
Maybe take a look at the following tutorial. It shows you the standard workflow for a response spectrum analysis. > Infocenter - Overview > Documentation - Tutorials > Building Design > Reinforced Concrete Building - Seismic Analysis and Shear Design (BIM Workflow)

In addition, you can check out what’s new for SOFiSTiK version 2022. Back then we introduced some important changes in the RSA workflow.

Mit freundlichen Grüßen
Frederik Höller
Ihr SOFiSTiK Support Team