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Old Seismic Values

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I have a project in a low/moderate seismic zone (moderate to high wind), and
the client specifically wants seismic calculations and details.  I was then
given this information as part of a larger report:


"The site is in seismic zone one (1).  However, the area is free of major
active fault structures and the region is relatively free of seismic
activity.  According to recent investigations, the area will experience
seismic forces with a maximum effective peak acceleration of 5% of gravity
and effective peak velocities of 1½ inches per second during any 50-year
period, at the 90% confidence level."


The 50-year/90% confidence is the design level in the UBC codes and the 1991
NEHRP / ASCE 7-95.  I'm pretty sure I know what "maximum effective peak
acceleration of 5% of gravity" and "effective peak velocities of 1.5 inches
per second" mean.  However, is there a relationship between these numbers
and UBC design values?  What about Aa and Av (older NEHRP)?  Ss and S1
(current NEHRP)?  

Any guidance as to where to look?

Specifically, I would like to give the client a comparison between the
values they gave me and values from FEMA 450/2003 NEHRP (Ss = 14%, S1=6%).

Thanks in advance.

---
Jason Kilgore
Leigh & O'Kane, LLC
Kansas City, Missouri




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