The Frequency Analysis Graph PropertyManager allows you to create plots of frequencies versus effective mass participation factors and cumulative effective mass participation factors.
To open this PropertyManager, run a frequency or linear dynamic study. Rightclick Results and select Define Frequency Response Graph.
Frequency vs.

Mode Number

Creates a line graph of resonant frequencies versus mode numbers. Lists the results under Summary. 

Effective mass participation factor (EMPF)

Creates a bar graph that shows the effective mass participation factors (EMPF) for the global X, Y, and Z directions for each mode. Lists the results under Summary. The effective mass participation factor represents the percentage of the system mass that participates in a particular mode. It provides a measure of the energy contained within each resonant mode. A mode with a large EMPF is usually a significant contributor to the dynamic response of a system.


Cumulative effective mass participation factor (CEMPF)

Creates a line graph that shows the cumulative effective mass participation factors for the global X, Y, and Z directions. Lists the results under Summary. Mass participation factors are important in determining how many modes should be considered to capture adequately the dynamic response of a structure. Many codes require that the number of modes considered must contribute to a CEMPF of at least 80% of the system mass in the direction of excitation.

Summary

Show Frequencies (Hz) where the EMPF is greater than:

Shows the frequency range where the effective mass participation factor (for the selected global coordinate direction) is greater than the % value you enter. 

Show Frequencies (Hz) where the CEMPF is greater than:

Shows the frequency range (min  max) where the cumulative effective mass participation factor (for the selected global coordinate direction) is greater than the % value you enter. 

X Y Z 
Select the global coordinate direction considered for the EMPF and CEMPF. 
Report Options

Save

Saves the results to a comma delimited *.csv file. Use a text editor or Microsoft Excel to view this file. 