16.11. Modal Response Spectrum Analysis

Try these first

1. 1.

   What does the Modal Response Spectrum Analysis help us to estimate?

   Hint

   Think about what happens to structures during an earthquake.

2. 2.

   Define what a response spectrum is.

   Hint

   Consider the relationship between period and response.

3. 3.

   What does the Response Spectrum Method estimate?

   • A. Peak response
   • B. Material failure
   • C. Design loads

   Hint

   Remember what aspect of seismic events we analyze.

4. 4.

   True or False: Modal participation factors are irrelevant to the total response of a structure.

   • True
   • False

   Hint

   Think about the role of each mode in a system!

5. 5.

   A building has a mode shape of 0.6, a modal participation factor of 0.5, and a spectral acceleration from the response spectrum of 2.0. Calculate the peak modal response.

   Hint

   Use the formula for peak response carefully!

6. 6.

   Consider a system with three closely spaced modes. Discuss how you would analyze their combined effect using both SRSS and CQC methods, considering their differences in accuracy.

   Hint

   Focus on understanding how the two differ when dealing with closely spaced frequencies.