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Re: Simpson Strongwall Question

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Dear Steve: 
As you mentioned, "current allowable shear values as set forth in the
building codes" are just that. Allowable shear values in the code are
for plywood, or OSB, by itself, with a specific nailing pattern, nothing
more. It is up to the Engineer of Record to check the overturning
stresses in the shear wall assemble, and all of it's parts. This
includes, but is not limited to, the following:
	1). The capacity of the end posts, in compression, when subjected to
vertical loads as well as simultaneous overturning forces. The Tables
that Simpson has produced, do not include the reduction due to vertical
Dead and Live loads, which must be added to the overturning force. This
should reduce the allowable capacity of the Strong Wall.
	2). The sill plate (or in the case of the Strong Wall, plywood and
floor joists at the second floor) and its related crushing (compression
perpendicular to the grain) due to overturning, and vertical loads
acting simultaneously. The Tables by Simpson seem to disregard this
second floor condition.

When I calculated the compression under the end posts I discovered that
it overstresses the plywood, and the joists below, in crushing (ie.
compression perpendicular to the grain), even with no vertical load is
added!! Let me know your thoughts on this.
		Best Regards, Jim