Shear and Flexural Strengthening of Masonry Infill Walls with FRP for Extreme Out-of-Plane Loading

Two series of walls, reflecting twelve un-grouted URM walls with different strengthening schemes using FRP composite materials were tested in this study. The results of the first eight specimens are presented in this paper. The walls were subjected to uniform loading along their height using high-pressure bags where the applied pressure could be controlled and monitored through failure. FRP composites in the form of rods and laminates were used as strengthening materials. Retrofit connections were evaluated at the top and bottom using two innovative boundary connections. The tests caused a well-distributed range of damage levels. Under a pilot field study the shear capacity controlled the blast behavior of the strengthened walls, a shear retrofit connection was also studied in the two series of tests. An analytical analysis using a single degree of freedom (SDOF) approach was used to predict the behavior of masonry walls strengthened with FRP.