Cyclic Load Testing of Unreinforced Masonry Walls

摘要

The report presents results of three laboratory experiments done to investigatein-plane lateral strength and behavior of unreinforced masonry walls. The parameters of the experimental study were the length-to-height aspect ratio of the test walls and the level of vertical compressive stress. Wall specimens were newly constructed using reclaimed brick and a mortar representative of older construction. Measured strength and behavior of the test walls is correlated with each other, with computational models and with estimates based on nondestructive measurements. Results of the experiments suggest that (a) an unreinforced masonry wall can resist more than twice the lateral force resulting in the first crack, (b) inelastic deformation capacity can be very large for walls that are cracked in both flexure and diagonal tension, (c) capacity for hysteretic energy dissipation can be large despite cracking, and (d) cyclic behavior can be represented in terms of behavior under monotonically increasing forces. These conclusions have an impact on the way that nondestructive measurements are extrapolated when diagnosing levels of safety for lateral strength of isolated walls as well as for complete building systems.