Experimental study on seismic behavior of steel reinforced recycled aggregate concrete frame infilled with recycled aggregate concrete hollow blocks

Based on the experimental study on four 1/2.5-scaled model of one-bay and one-story steel reinforced recycled aggregate concrete frames infilled with recycled aggregate concrete hollow blocks under low cyclic reversed loading, the effects of masonry strength, axial compression ratio and lacing rebar spacing on seismic behaviors of specimens were investigated. The failure mode of the structure, load-displacement hysteretic loops and skeleton curves, load carrying capacity, inter-story drift ratio, displacement ductility, energy dissipation and stiffness degradation were analyzed. The results indicate that infilling walls fail earlier than frames. The failure mechanism is the beam-hinged mechanism. The hysteretic loops are in a plump-shape. And the capacity of energy dissipation is better. With the decrease of infilling blocks strength, the load carrying capacity decreases, displacement ductility increases, initial stiffness decreases and the stiffness degradation turns slow. The inter-story drift ratio and equivalent viscous damping coefficients increase at failure point. With the increase of axial compression ratio, the load carrying capacity increases, displacement ductility decreases, initial stiffness increases obviously and the stiffness degradation turns fast. The inter-story drift ratio and energy dissipation decrease at failure point. With the decrease of lacing rebar spacing, the load carrying capacity and displacement ductility increase slightly, initial stiffness increases but the stiffness degradation speed keeps almost constant, and the inter-story drift ratio and energy dissipation increase at failure point.