A modal analysis allows for the dynamic analysis of structural systems capable of vibrating. As a result, natural vibration values are determined, such as natural frequency, a mode shape, modal mass, and effective modal mass factors.
The modal analysis is the basis for further dynamic analysis, such as for loading by a response spectrum or a time diagram. This is a completely linear method; the nonlinearities existing in the system are not taken into account.
Modal Analysis Add-on
A modal analysis can be performed in RFEM or RSTAB using the Modal Analysis add-on. In addition to the results of modal parameters in tables, the natural vibration modes are also available graphically for the evaluation.
Furthermore, the modal analysis represents a method for solving time history. In this case, the determined eigenvalues and mode shapes of the model are directly used.