Influence of Wall Openings on Nonlinear Lateral Load Response of Reinforced Concrete Frames with Masonry Infills: A Finite Element Study

In the present study, a simplified finite element micro-modeling technique was developed for the in-plane cyclic lateral load analysis of reinforced concrete frames with masonry infill walls having openings. Such frames are commonly constructed in several countries, and if not constructed properly, tend to get damaged during earthquakes thereby increasing the seismic risk in the region. Results of the numerical studies showed the effectiveness of using the simplified finite element micro-model in accurately predicting their lateral load responses. A finite element parametric study was undertaken to understand the influence of size and location of openings in masonry infill walls and aspect ratio of the reinforced concrete frames on lateral load response of infilled frames. Though the aspect ratio of the frame and size of the openings were found to have a significant effect on the lateral load characteristics of the frames, such as, lateral strength, lateral stiffness, and energy dissipation capacity, the influence of location of opening on these parameters was limited. It was also observed that the contribution of masonry infills reduced significantly when size of the opening in the wall was more than 20%. Further, the influence of horizontal eccentricity in the wall openings was found to be insignificant for most of the studied frames.