M. To calculate the structure frequency
To calculate the frequency of the structure for a load case, use the following procedure.
Frequency
calculation is made for a specific load case, so you must have at least one
primary load case added to the input file.
This can be done
by either the Rayleigh method or the eigenvalue extraction method. The latter
can consider missing mass mode.
-
Either:
The Add New Load Items dialog opens.
On the Loading ribbon tab, select the Load Items tool in the Loading Specifications group
Tip: This will add the load item to the currently selected load group selected in the program status bar.or
In the Load & Definition dialog, select a primary load case in the Load Cases Details list and then click Add.
- Select either:
- (Optional) For Modal Calculation, check the Consider Missing Mass option to include the missing mass procedure for steady state or harmonic analysis.
- Click Add. The frequency calculation is added to the load case.