Seismic performance of joist-pocket connections. II: Application

It has been known for some time that connections in unreinforced masonry structures play a major role in the performance of such structures. Few attempts have been made to analytically address these components. An' understanding of these "pocket" connections will allow for better estimates of the behavior of brick buildings and provide a useful tool for the design of seismic retrofit details. Previous investigations have centered on the linear or nonlinear response of the brick walls themselves, or the floor and root diaphragms. The movement between the floor and roof diaphragms and the wall has not been previously considered. (A companion paper presented the development of a technique for the examination of the seismic performance of joist and beam bearing connections in unreinforced masonry structures.) A historic brick building that was shaken during the Loma Prieta earthquake of 1989 is modeled herein using this approach. The effect of motion at the diaphragm-to-wall interface is discussed. A discussion of the importance of several parameters, including bearing length, coefficient of friction, coefficient of restitution, and distance from end of joist to end of wall is presented.