A double-strut macro-modelling approach for the in-plane analysis of masonry infilled RC frames with openings

Based on experiments and micro-modelling analyses, the interaction between the RC frame and the infill wall with/without openings under lateral loads was investigated. According to the load transmission mechanism and the stress states around the openings, a macro-model with multiple blocks around the opening was proposed. In a comparison with the experimental data, the proposed macro-model was proven to adequately simulate the different failure modes and hysteretic behaviours of masonry infilled RC frames with openings. By using the opening rate and opening position as variables, 52 macro-modelling analyses of masonry infilled RC frames with different window and door openings were carried out. The results showed that the presence of masonry infill walls greatly increased the initial stiffness and ultimate load bearing capacities of single-story, single-bay RC frame structures. A larger opening rate resulted in lower initial stiffness and ultimate load-carrying capacity values, which decreased more as the opening locations deviated further from the centre to the sides.