Strengthening of unreinforced masonry walls using FRPs

An experimental program conducted at the University of Alberta showed that externally applied fiber reinforced polymers (FRPs) are effective in increasing the load-carrying capacity of unreinforced masonry walls that are subjected to out-of-plane flexural loads. Ten walls with a height of 4 m were used to conduct 13 tests in two series. Both undamaged and slightly damaged walls were tested. The following experimental parameters were investigated: (1) type of fiber reinforcement; (2) amount of fiber reinforcement: (3) layout of fiber reinforcement; (4) effects of moderate compressive axial load; and (5) cyclic behavior. This paper briefly reviews the existing rehabilitation methods available and explains why the use of FRPs as external reinforcement is a possible alternative. The test setup and instrumentation of the specimens are described followed by a discussion of the results. The general behavior of the specimens is discussed with emphasis on the load deflection and strain characteristics. The modes of failure are identified and categorized. Finally, a simple analytical model is proposed and compared with the test results followed by a summary of the major results.