modal excitation factor for rotational degrees of

[ag110]

Dear colleague

Would you please inform me what is your reference for calculating modal excitation factor for rotational degrees of freedom? and if you have simple example I appreciate if you share it.

Best Regards

[z.gronti]

Dear ag110,
The modal excitation factor is calculated through the type Ln=(Ön)T*M, where M is the mass and (Ön)T the traspose vector of the mode shape. You may find examples in any good textbook on Structural Dynamics.

[ag110]

thanks for your reply
but my problem is calculating modal excitation factor for rotational degrees of freedom when lumped mass is used in the model.