Abstract
This report summarizes a seismic structural retrofit to an existing unreinforced masonry (URM) building in Placerville, California, presenting two different structural systems as alternatives. The first system is a more traditional approach using a Special Steel Moment Resisting Frame (SMRF), while the second features a newer approach of coating the walls in Fiber Reinforced Cementitious Matrix (FRCM). The various failure modes and concerns of URM buildings or components subjected to earthquake excitation are presented, along with the different design methodologies of the two retrofit strategies. A comprehensive literature review is presented to establish the design methodology and material characteristics for the FRCM to determine the upgraded strength of the masonry structure. For both systems, the diaphragms are also detailed according to the varying seismic forces developed from each lateral load resisting system.