response spectrum analysis

huangyhg

response spectrum analysis
i was asked to do response spectrum analysis on a certain industrial related structure but i am not really sure of the exact/step by step procedures or solution of such problem. i have done some modal analysis of turbine/blower foundations by just calculating the natural freq. of the foundation and comparing it to the natural freq. of the machine to check for resonance. is this procedure the same also with response spectrum analysis? i have listed the following procedure i know and i want to hear any advise/supplements from anyone knowledgeable on this subject.
1. prepare mass model
2. prepare response spectrum load
3. perform response spectrum analysis
4. calculate natural freq. of the structure
5. after calculating the n.f. of the structure, what is the next thing to do? where will i compare the n.f. of the structure to check for resonance?
thank you very much!
the response spectrum is then compared to both the nf of the structure, the harmonics of the nf, and to the critical components or machinery.  the values are compared to published data (for structures, richart, hall, and woods is a good source....for machinery or equipment, the manufacturers should know the limits)to check for damage potential, resonance potential, or "irritation" considerations.