Performance Testing of Fiber-Reinforced Polymer Composite Overlays for Seismic Rehabilitation of Unreinforced Masonry Walls

摘要

A large portion of the Army's facility inventory incorporates load- bearing unreinforced masonry (URM) walls. Because this type of structural system has been shown to perform poorly in past earthquakes, structural upgrade technology is needed to protect facility occupants and mission-critical operations during and after seismic activity. This research investigated procedures for strengthening masonry walls using readily available advanced composite materials systems. New 4 x 4 ft wall panels of double-wythe brick or concrete masonry unit (CMU) construction were reinforced with FRP composite materials applied to one face. These wall specimens were tested to failure on a million-pound load test machine at the U.S. Army Construction Engineering Research Laboratory (CERL). Load tests also were performed on FRP-reinforced standard masonry prisms, and shear tests were conducted on different widths and thicknesses of FRP composite applied across the mortarjoints of brick triplets. FRP composites show great potential for seismic hardening of URM walls. Triplet tests demonstrated consistent strengthening of the mortar joints as a function of the width and thickness of the FRP composite overlay.