Experimental Analysis of Surface Application of Fiber-Reinforced Polymer Composite on Shear Behavior of Masonry Walls Made of Autoclaved Concrete Blocks

This paper presents the results of an experimental study of the shear behavior of masonry walls made of aero autoclaved concrete (AAC) blocks strengthened by externally bonded fiber-reinforced polymer (FRP) composites. Fifteen small wall specimens were constructed and tested in a diagonal compression scheme. Two types of composite materials—carbon- and glass-reinforced polymers—were arranged in two configurations of vertical strips, adopted to the location of the unfilled head joints. The effect of the strengthening location and strengthening materials on changes in the strength and deformability parameters are discussed and the failure process of unstrengthened walls is also presented. The placement of the composite on unfilled head joints proved to be a better solution. Carbon-fiber-reinforced polymer (CFRP) strips provided a threefold increase in stiffness, a 48% increase in load-bearing capacity and a high level of ductility in the post-cracking phase. Glass-fiber-reinforced polymer (GFRP) strips offered a 56% increase in load-bearing capacity but did not change the stiffness of the masonry and provided relatively little ductility. Placing the composite between unfilled joints was only reasonable for CFRP composites, providing a 35% increase in load-bearing capacity but with negligible ductility of the masonry.