The manual does not say anything about the method used by CAESAR for dynamic calculations by Time History.
The question is:
Does CAESAR convert the Time History into a spectrum and then performs a spectral modal analysis?, or if it directly performs the dynamic calculation with the Time History.
Thank you very much.

If you select "Time History" as the analysis type, CAESAR II performs a time history analysis. The time history pulse is not being converted in to a spectrum.

As mentioned before by Mr Richard . If you select time history as the analysis type in main window pull down menu Caesar performs a time history analysis.

Dynamic excitation spectra are to be defined as force-time profile which are than applied on pipe elbows/tees.

Here we can simulate the system response at all time periods as per our requirement. Time period can be sliced to several time steps.