Seismic Resistance of Wood Shear Walls with Large OSB Panels

Abstract

Results are presented from studies on the seismic resistance of wood shear walls sheathed with large (2.4 × 2.4 m) and standard (1.2 × 2.4 m) size oriented strand board (OSB) panels. Comparisons were made among twelve 2.4 × 2.4 m walls tested under quasi-static monotonic and cyclic, as well as dynamic, loads. In push-over tests, all walls reached a drift of approximately 2.5% at maximum load. A 26% increase in shear capacity was achieved using large panels. The nails that would be at internal seams in walls with standard panels were redistributed around the exterior edges of some large panel walls. They also showed a 104% increase in shear capacity and a 30% increase in initial stiffness. These walls performed significantly better when tested dynamically, using the east-west motion recorded at Joshua Tree Station during the 1992 Landers, Calif., earthquake. Their maximum drift was reduced by approximately 25% over standard walls. Damage incurred during dynamic tests consisted mainly of nail pullout and tear out. Renailing at these locations is simple and can restore the wall to a satisfactory performance level.