Modeling the seismic actions in the FEM program requires the knowledge of the time evolution of acceleration at the bottom boundary being represented by an accelerogram - a record of time instances and corresponding values of instantaneous acceleration.
Three options to specify accelerograms in the "Earthquake" frame are available:
- Generate a synthetic accelerogram with corresponding response spectrum;
- Upload the recorded accelerogram from an external data file;
- Create own accelerogram
The accelerogram is interpreted as a piecewise linear distribution of acceleration. The user should ensure (verify) that the uploaded or defined accelerogram results in zero value of the velocity at the end of the record.
The generated accelerograms comply with this condition.