The calculation of Eigenvalues is the first step in many dynamic calculations. Despite it involves advanced structural engineering concepts not always studied in deep in some civil engineering courses it is quite simple to do frequencies analysis in RM Bridge within OpenBridge Designer.
Since the Modal Analysis is generally a good indication of the model behavior it is also used just to check the structure. Therefore, as shown below, now the user has an option to automatically include it in the Structure Check when using the Recalculate Modeler and going from the Modeler to the Analyzer.
Note that the user defines another Schedule name with a specific Stage for the Modal Analysis and the load case where all defined masses will be accounted for the stiffness that will be calculated based on all the structural input. We still suggest using the default method for more specific analysis with partial or deactivated elements. Frequency studies consider an Effective Mass, where the spring and mass system ignores any possible spring masses and has only the main element's masses.
More information can be found at the links below:
Mass Participation factors:
Training 5 for Seismic: