Filling a frame (whether reinforced concrete or steel) with an infill wall (whether masonry or concrete) is a common practice in retrofitting existing frames to withstand seismic loads that were not previously anticipated when the frame was designed. This work started with a major experimental program funded by California Transportation Department (CalTrans) and was finalized by the numerical model designed by the author and presented in this book. This numerical model was the benchmark used to perform a parametric analysis studying several factors affecting the properties of the reinforced...