Strength of Timber Roof Connections Subjected to Cyclic Loads

摘要

The investigations described in this report examined the adequacy of typical timber roof connections used in masonry housing construction in resisting forces developed during earthquake ground motions in the less seismically active areas of the United States. Displacement controlled load tests using both in - plane and out - of - plane forces were performed on five basic types of roof - to - masonry wall connection mockups comprising a total of 19 models. The five types of connections contained load - bearing and nonload - bearing connection details of both gabled truss and flat roof construction. Test results indicated that the connection of the truss rafters to bearing and nonbearing walls was adequate. However, supplementary anchorage devices need to be used for connections employing ledgers, since bolts tend to fail by pulling out of the face shell of the masonry units and ledgers fail easily when subjected to cross grain tension. Graphs, drawings, and photographs are used throughout the report and a total of 19 references are provided. (Author abstract modified).