Out-of-Plane Behavior of URM Walls Strengthened with Fabric-Reinforced Cementitious Matrix Composite

The use of unreinforced masonry (URM) walls is common practice in different types of construction, such as interior or exterior walls. URM walls are typically deficient in flexural capacity when subjected to out-of-plane loading caused by high wind pressure or earthquakes. Retrofitting masonry walls with novel materials, such as fiber-reinforced polymer (FRP) composites, has shown enhancement of the flexural capacity and pseudoductility. This study evaluates the feasibility of fabric-reinforced cementitious matrix (FRCM) as an alternative external strengthening technology to improve out-of-plane behavior of URM walls. This paper reports experimental results on flexural capacity of nine clay brick walls of which six were strengthened with two different amounts of FRCM, namely one and four reinforcement fabrics. Experimental evidence shows significant improvements in the structural performance in terms of flexural capacity and stiffness of the strengthened walls. An analysis, disregarding arching effect, is conducted, and its results are compared with the experimental database. From here, the design limits are discussed. Finally, experimental data from other research programs using FRP are reported to show that when flexural capacity is related to a calibrated reinforcement ratio, the two technologies are equivalent.