In-Plane Seismic Strengthening of Masonry Walls with Sprayed Glass Fibre Reinforced Polymer

The need of strengthening old masonry structures is becoming more apparent, particularly in seismic areas. This experimental investigations focus on the seismic behaviors of unreinforced masonry walls strengthened with Sprayed Glass Fiber Reinforced Polymer (SGFRP). The strengthening was attained by spraying the mixture of resin and catalyst with chopped glass fibres onto the masonry wall surface, combined with layers of GFRP mesh fabric. The testing program of four masonry wall specimens subjected to the quasi-static, cyclic in-plane shear loads combined with a constant gravity load is reported, which is to clarify the failure mode of strengthened walls, and the effects of different spraying thickness and different glass fibre length on the in-plane shear loading capacity and resistance of lateral deformation. The test results show that the proposed retrofitting technique is highly effective for seismic strengthening masonry walls, and a specimen with the fibre length of 25mm and spraying thickness of 7mm behaved perfectly. In addition, the calculation results of shear strength of strengthened walls prove to be considerably in accordance with the test results.