In-Plane Shear Behaviors of Constrained Masonry Walls Externally Retrofitted with BFRP

Abstract

This study presents an experimental study on responses of eight constrained masonry walls with tie columns and ring beams, subjected to in-plane cyclic loading before and after being retrofitted with basalt-fiber-reinforced polymer (BFRP). Among these eight walls, two without any strengthening measures served as reference specimens; two were directly strengthened with horizontal and diagonal BFRP strips after they were constructed; and the rest were tested to defined damage levels and then repaired for retesting. The opening in the wall, the layer of the BFRP strip, and the vertical compression level were considered in the test design. Experimental results showed different failure modes of the specimens. Details of testing results were discussed regarding strength and drift, hysteretic characteristics, stiffness degradation, energy dissipation, and BFRP strip strains. A performance comparison analysis was also conducted between the constrained masonry walls and the unreinforced ones. Finally, a calculation method was proposed to estimate the ultimate lateral strength of BFRP retrofitted masonry walls.