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FEMA 310

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Okay-
I am doing a FEMA 310 evaluation on a single story wood framed
building.  FEMA 310 building type W1.

When figuring the pusedo lateral force per 3.5.2.1, you are allowed to
use V=.75W per equation 3-2.

The m-factor is to be taken a 1.0.

This of course results in some very high base shears used for evaluation
purposes.  1994 UBC allowable stress design base shears are of course
V=.1375W, 5 1/2 times lower than the FEMA 310 numbers.

Here is the rub, when going through the Tier 1 checklists, plywood shear
walls that have shears in excess of 1000 plf based on the V=.75W are
designated as not adequate for life safety.  If your shear walls are not
designed at a working stress level for anything greater than 200 plf,
then I guess you might be uncovering a real potential problem.  However,
this is not normally the case.  Plywood shear walls are frequently
designed for working stress loads around the 500 plf to 700 plf range,
and even higher on occasion when plywood is put on both sides of the
wall.

This FEMA 310 procedure ends up "tagging" almost every single wood
framed building designed to current 1994 UBC levels for a FEMA 310 tier
2 evaluation.  This would seem like a waste of the owners money.

Is a single story wood framed building designed to the 1994 UBC
requirements capable of providing a life-safety level of protection in
seismic zone 4 or not?

Am I missing something?

Please help!!!

Lynn