Experimental study and design of a new hybrid RC frame system with stiffened masonry wall subjected to cyclic loading

Abstract

Summary This paper experimentally investigates the hysteresis behavior of a hybrid reinforced concrete (RC) frame system with stiffened masonry wall to enhance the seismic performance of existing RC buildings subjected to cyclic loading. The influences of the depth of the columns section, the length of masonry walls, and the grouting ratio of reinforced masonry were evaluated by designing a series of orthogonal quasi‐static tests on a half‐scale specimen. Test results indicated that the grouting ratio played the most significant role on the maximum strength, energy dissipation capacity, and the relative stiffness degradation rate of the hybrid structural system, whereas the length of masonry walls tends to dominate the deformation capacity. A trilinear analytical model and design recommendations are proposed to estimate the cyclic behavior based on force‐displacement hysteresis law that takes account of the effects of the post‐peak strength and unloading stiffness degradation.