Epoxy bonding a thin layer of composite materials to the exterior surfaces of unreinforced masonry (URM) walls forces the individual brick or block elements to act as an integrated system. The high tensile strength of composite materials can be utilized to increase the shear and flexural capacity of URM walls significantly. This article presents the results of the experimental work carried out to investigate the capability of glass fiber reinforced polymer (GFRP) laminates in strengthening the concrete block walls subjected to out-of-plane and in-plane vertical and lateral stresses. A significant strength increase was observed for all strengthened specimens. Based on deformation compatibility and force equilibrium, simple design equations are presented to estimate the strength of masonry walls and their possible mode of failure. An excellent agreement between measured and predicted values of ultimate strength of wall specimens has been observed.
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