Experimental diagonal tension (shear) test of Un-Reinforced Masonry (URM) walls strengthened with textile reinforced mortar (TRM)

Abstract

The presented study is part of ongoing experimental program on Un-Reinforced Masonry (URM) walls strengthened with Textile reinforced mortars (TRM). Ten walls were tested under diagonal tension (shear) test method in order to consider the effect of strengthening system on the behavior of brick walls. One plain wall was tested as reference. Two walls were overlaid with 15 and 25 mm thick of high strength mortar on one face without any textile sheet. Another seven walls were externally strengthened with 15 and 25 mm thick of AR-Glass Textile Reinforced Mortar (TRM) on one or both faces. Results confirmed the efficient possibility of shear strengthening of existing URM walls using TRM, especially for those strengthened on both faces. On the other hand, one face strengthened walls were sensitive to the applied load and can buckle or experience out-of-plane deformations. TRM extremely improved diagonal load carrying capacity and deformation capacity, which caused the strengthened walls fail in a ductile manner. The governing failure mode was out-of-plane deformation for one face strengthened walls, and failure of both faces strengthened walls was controlled by initiation of substrate toe crushing in compression continued by diagonal crashing. Results showed that for masonry walls strengthened on both faces, during pure in-plane diagonal load, there is no need to mechanical connection between TRM and masonry substrate. However, out-of-plane failure is an important issue for masonry walls, especially for those strengthened on one face. Therefore, connectors must be designed for out-of-plane lateral force to ensure that masonry wall and TRM reinforcement layer work together properly.