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Wall Anchorage to Flexible Diaphragms

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I have a question regarding interpretation of 1997 UBC 1633.2.8.1
subparagraph 5, where wood members provide lateral support of masonry in
seismic zones 3 and 4. This paragraph calls for a .85 factor on lateral
loads and mandates minimum 2-1/2" width for all wood elements of the wall
anchorage system.

Does this paragraph only apply to supporting wood members when using LRFD
design of wood? Or is it meant to apply to wood members generally, where the
forces referred to start out as ultimate loads and are then converted to
working stress, i.e. "E" loads which become E/1.4 in the allowable stress
load combinations?

I have a small masonry building with a pitched roof in zone 3 with
premanufactured roof trusses at 24 inch intervals. The seismic forces from
the masonry would be transferred to the roof diaphragm via the truss top
chord using Simpson HETAL clips at the ends of the trusses. Am I required to
use 2-1/2" wide top chords to comply with this section? A similar situation
arises where joist and ridge beam framing is used for the roof. 

Jim Lutz
Earth Tech - Bellevue, WA