Performance of low-carbon textile-reinforced mortar: Out-of-plane response of strengthened masonry walls

Unreinforced masonry (URM) walls are highly susceptible to seismic events, especially in the out-of-plane direction, due to their weak tensile and flexural behavior. Moreover, the concrete industry is responsible for a large amount of CO2 emissions generated during the production of Portland cement. In response, the current study aims to investigate the out-of-plane response of URM walls externally strengthened with Textile Reinforced Mortar (TRM) where cement is partially replaced with natural zeolite. Eight double-wythe width brick walls were tested under three-point bending tests; including one reference wall and seven walls externally reinforced with different TRM configurations. Investigated parameters comprised of the number of textile layers, application on one or both faces, proficiency in using connectors, and the effect of natural zeolite as a substitution for cement. In addition, a series of tensile tests was also included as a part of the experimental campaign for further investigation of the interaction between textile and mortar in tension. Different proportion of the cement was replaced with natural zeolite to evaluate the effect of zeolite-based mortars on bonding between textile and mortar. Results of the three-bending test evidenced a significant increase in load-bearing capacity and ductility of reinforced specimens. The application of TRM with different reinforcement ratios indicated a direct impact on peak load. Connectors enhanced flexural capacity by providing better bonding between TRM and substrate. Natural zeolite in the TRM composition caused a reduction in terms of strength. Tensile tests consistently showed that the ultimate strength decreased as the amount of zeolite increased by 20% substitution. The results of the existing experimental data were evaluated against the analytical method presented by this study to determine the performance of each parameter.