A novel parallel wire steel-reinforced mortar (PW-SRM) method versus textile reinforced mortar (TRM) for out-of-plane strengthening of masonry walls

Abstract

Lateral loads cause extensive damage to buildings due to the weakness of bearing out-of-plane un-reinforced masonry (URM) walls. Strengthening URM walls is consequently favored by researchers aiming at achieving building and respective occupant safety. The strengthening of masonry structures with textile reinforced mortar (TRM) or steel-reinforced mortar (SRM) has become prevalent in the last two decades. This study presents an innovative method of strengthening masonry walls using mortar reinforced with high tensile strength steel (HTSS) parallel wires. For the first time, an unprecedented investigation as to the effects of the grooving method improving the load-carrying capacity and failure mechanism of masonry walls under out-of-plane loading was performed. In addition, the parallel wires steel-reinforce mortar (PW-SRM) was compared with the textile-reinforced mortar (TRM) reinforcement method. Nine walls with dimensions of 1400 × 440 × 100 mm each were reinforced through different techniques and tested under four-point out-of-plane bending. The implications of the number of glass textiles with open mesh layers, one-sided and two-sided reinforcement, engineered cementitious composites (ECC), grooves on the masonry substrate, and, the volume of HTSS wires in increasing out-of-plane loading were compared and discussed. The findings demonstrated that the best performance is related to the specimens reinforced by the PW-SRM method. Similarly, the amount of out-of-plane load-bearing capacity and energy absorption increased more than 24 and 5300 times compared to the control specimen, respectively. It was further discovered that the grooving method transferred the tensile stress created in the TRM composite to the depth of the masonry substrate, which enhanced the failure mechanism from debonding to textile rupture and increased the strength by 88% compared to the corresponding specimen without grooves.