Finite-Element Modeling of Hybrid Concrete-Masonry Frames Subjected to In-Plane Loads

Caribbean-style hybrid concrete-masonry structures consist of a RC frame infilled with partially grouted and reinforced masonry walls that are connected to the RC frame with cast-in-place dowels along one or more edges of the infill. Currently, there is little guidance in existing codes for the assessment of infills with such connections to the bounding frame. This paper proposes a finite-element modeling scheme for hybrid concrete-masonry structures combining smeared crack and interface elements. The model is used to predict the behavior of two hybrid concrete-masonry frames subjected to cyclic loading. The proposed finite-element modeling scheme closely predicts the peak capacity, the displacement at peak capacity, and the damage patterns of the test structures. Finally, sensitivity studies are conducted with the validated numerical models to investigate the influence of the dowel connections and masonry properties on the seismic performance of these structures. The results indicate that increasing the amount of reinforcement in the masonry infill makes the influence of the dowel connections become more pronounced, increases the strength of the structure, and lowers its ductility.