Performance of bolted wood connections using supplemental confining devices

Abstract

In the aftermath of the 1994 Northridge Earthquake, extensive field investigations revealed damage in wood frame construction in the form of splitting the 2x4 or 2x6 dimension lumber sill plates along the line of anchor bolts which typically connect shear walls to the masonry or concrete foundation. This paper presents an experimental investigation on the performance of bolted wood connections at the yield and ultimate limit states during monotonic and incremental quasi-static reversed cyclic loading and suggests possible retrofit strategies for their improved seismic performance. Proposed retrofit strategies are based on providing confinement to the bolted wood member using metal reinforcing ;traps and reinforcing clamps to increase the deformation capability and energy dissipation capacity of the connection, while maintaining substantial levels of connection strength. Connection types included in the investigation are: (1) double shear wood-to-wood connections; and (2) single shear simulated sill plate-to-concrete foundation connections.