Post-frame construction has the potential to make significant gains in commercial and institutional markets because of the inherent advantages in its unique steel-clad, wood-framed structural envelope system, which resists lateral loads, including wind and earthquakes. Lateral design methods for post-frame buildings are available. Lacking, however, are actual performance data on steel-clad, wood-framed diaphragms and shear walls.
In the first phase of this project (completed in the first half of 2012),18 tests were completed, and the results provide the industry with much-needed data for shear values that previously had not been available. Critical variables tested include girt spacing, screw patterns, number and type of fasteners, and rib patterns. Post frame now offers a range of values and assemblies that did not exist previously.
The second phase of this project (conducted in the second half of 2012), involved experimentally measuring the shear strength and apparent shear stiffness of common constructions of steel-clad, wood-framed diaphragms under monotonic loading.
Tests of 11 different roof assemblies have been completed. Data from the tests have been submitted, and a draft report has been completed. Remaining material will be used for testing three additional conditions in January. Discussions will be held regarding the best way to incorporate these results into ASABE EP 484, used by engineers to support the design of post-frame construction.