There is an interesting paper in the Journal of Structural Engineering, Vol.
119, No. 5, May, 1993.
Title "Lateral Load Sharing by Diaphragms in Wood-framed Buildings" By
Timothy L. Philllips et al
The complete abstract follows.
Abstract: Current analysis and design procedures for light-frame wood
buildings do not give consideration to the complex three-dimensional
structural response of the buildings. A full-scale single-story wood house
is constructed and tested under lateral loads at various stages of loading
to evaluate the structural response and load-sharing characteristics.
Different sheathing, fastener arrangements and openings are incorporated to
create shear walls with varying stiffness. Extensive force and displacement
reading are made of the building during testing to quantify the structural
response. Results of the study indicate that the roof diaphragm behaved
nearly like a rigid diaphragm. Load distribution among the shear walls is a
function of wall stiffness and position with in the building. The walls
transverse to the loading direction carried between 8% and 25% of the
applied lateral load. Stiffness contributions provided by additional layers
of sheathing are directly additive.
Note the roof system consisted of W trusses. See the entire paper for more
Daniel McNaughton S.E.
4455 Murphy Canyon Rd, Ste 100
San Diego, CA 92123