Dear Peter

These are my remaining queriesI could not put all of them in one post)

3.What do you mean by "There is not much energy in the earthquake above 10 Hz so .003 s is a reasonable time step."? How do you conclude that 0.003sec is good by the little energy content above 10HZ? (I drew the fourier amplitude-frequency graph by seismosignal and observed that the vast majority of the seismic energy is below 10Hz).

4. How do you apply the 10sec-static gravity load in step one?(at t=0, acceleration(y)=0 or 9.8066m/s2?)

5. I ran the analysis(it took 12 hours!!), but it did not converge...I need its results to verify my geometry. what should I do?Could you please help me?

In this regard, I have attached my model to benefit from your kind guidance(please consider the ansys file attached to my first post in this topic as I can not attach files anymore....).

Best Regards