Seismic Behavior of Masonry Walls: Modeling of Hysteretic Rules

Abstract

A method of modifying the lateral load–lateral displacement relationship obtained by a simple monotonic racking test to represent the skeleton hysteresis curve of an arbitrary dynamic response of a reinforced-masonry wall is proposed. The results of tests of 32 equal reinforced-masonry walls, tested by imposing monotonically increasing displacements, cyclic lateral displacements of two different shapes, and simulated displacement seismic response, have been used as a basis for the development of the procedure of modification. The amount of input energy, defined as the actuator work done to deform the specimens during the test, has been taken into account as the decisive parameter for carrying out this modification. On the basis of experimental results, correlation factors between the monotonic and cyclic hysteresis envelope curves, as well as stiffness and strength degradation parameters, which define the hysteretic rules, have been evaluated. Good agreement between predicted and experimental cyclic behavior of the walls has been obtained.