Experimental study on seismic performance of damaged masonry walls reinforced with high-polymer cementitious composite material

Masonry structures are one of the most traditional and economical structural forms that are extensively used worldwide. However, severe damage to the masonry structures during past earthquakes addresses their vulnerability to seismic loadings. Therefore, it is critical to develop effective and efficient seismic reinforcement measures for masonry structures. This study proposes a structural retrofitting method for masonry walls that employs a corrosion protection liner (CPL) and high-polymer cementitious composite material (HPCCM). Cyclic in-plane pseudo-static tests were performed on six masonry wall specimens comprising three unreinforced and three seismically damaged masonry walls retrofitted with CPL-HPCCM. This experimental study explored the hysteretic behavior, deformation capacity, and failure mechanism of masonry wails after rehabilitation with the proposed retrofitting method under cyclic loading. The test results indicate that the CPL-HPCCM structural retrofitting method is an effective structural retrofitting technique that significantly enhances the lateral load-bearing capacity and energy dissipation capability of masonry walls. Even for the severely damaged masonry wall specimens, the lateral load-bearing capacity, lateral stiffness, and overall ductility of the wall specimens after retrofitting with CPL-HPCCM were restored to or improved beyond those of the intact wall specimens. Compared with the non-retrofitted specimens, the lateral load-bearing capacity of the CPL-HPCCM retrofitted specimens exhibited a substantial improvement, with a minimal increase of 14.6 %. In addition, the CPL-HPCCM method also enhanced the energy dissipation capacity of the wall specimens over 1.95 times compared to the non-retrofitted specimens. Finally, a lateral load-bearing capacity prediction equation was proposed for CPL-HPCCM-reinforced masonry walls based on experimental results.