Effects of textile-reinforced concrete on the cyclic shear behavior of damaged confined brick masonry walls

Abstract

Masonry walls are very fragile and prone to damage from the effects of earthquakes. However, after an earthquake, some of confined walls can continue to carry loads after repair and reinforcement. Strengthening is an effective measure for improving the seismic performance of damaged walls. In this study, the seismic performance of textile-reinforced concrete-strengthened damaged masonry confined walls was experimentally investigated. Apparently cracked and pre-damaged confined brick masonry walls were repaired and retrofitted with TRC (textile-reinforced concrete). The effect of anchoring on improving seismic performance was investigated, and a restoring force model of damaged confined brick masonry walls reinforced with TRC was established. The damaged masonry confined walls reinforced by TRC had better integrity and ductile behavior during the failure model, compared with unreinforced walls. Load-displacement curves of walls reinforced with TRC exhibited good postpeak behavior, and they had higher shear capacity, ductility factor, and energy dissipation. TRC surface reinforcement could provide a good restraint to damaged walls and improve the brittle failure characteristics of the walls. The number of cracks in each wall was significantly reduced, and the rate of decrease of stiffness was slowed down. For different strengthening methods, the initial stiffness, shear capacity, ductility factor, energy dissipation increased by 0.08-0.52, 0.04–0.22, 0.019–0.55, and 0.33–0.91 times, respectively, compared with unreinforced walls. Additionally, the application of anchorage measures significantly improved the shear bearing capacity and energy dissipation of the reinforced walls. Based on the experimental results, model curves of the restoring force of TRC-strengthened damaged masonry walls were given and analyzed according to the experimental results.