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Drift and Deflection ASCE 7-10 Table 12.12-1

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bigmig

Structural
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Aug 8, 2008
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I'm hoping someone can identify this easy question. Table 12.12-1 of ASCE 7-10 gives allowable story drift for seismic loading.
Appendix C references the ASCE Task Committee on Drift Control, and states the commonly publicized drift limits for buildings as somewhere between L/600 and L/400.

The difference between Table 12.12-1 is a factor of 10. Am I reading this right in assuming that Table 12.12-1 is for seismic loading only and that
for other loads (like wind), I should be sticking to the L/400 to L/600 range?
 
The drift limits are for seismic only and include the deflection amplification factor, Cd. This computed deflection is not a service load deflection, it is an "ultimate" deflection. The ratios you have indicated for wind design are for wind service loading, more of an "allowable" load case versus a "strength" load case multiplied by Cd.

That's why the factor of 10.
 
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