Experimental study on shear behavior of GFRP bars and high-strength thermal insulation mortar strengthened brick masonry walls

The shear behavior of brick masonry walls reinforced with Glass Fiber Reinforced Plastic bars and high-strength thermal insulation mortar (GHM) is crucial to determining whether this technique can be applied to integrated thermal insulation and strengthening retrofit projects of masonry structures. Through diagonal compression test, this study investigated the shear behavior of GHM reinforced brick masonry walls, specifically analyzing the effects of masonry mortar strength, volume volume replacement percentage of insulation materials, glass fiber reinforced plastic (GFRP) bar diameter, and GHM-strengthened layer thickness on the shear strength enhancement. Research results indicate that GHM-strengthened brick masonry walls show improved integrity and ductility compared to unreinforced masonry (URM) wall. The bearing capacity, shear strength, and post-cracking displacement of the strengthened specimens were significantly enhanced. Additionally, the load-displacement curves of the strengthened specimens exhibited improved post-peak behavior. After GHM strengthening, the peak load and its corresponding displacement of the specimens increased by 14.02 times and 4.09 times, respectively. The shear strength, ductility factors and energy dissipations increased by 2.42–7.62 times, 2.14–4.68 times, and 21.47–29.10 times, respectively. Based on the analysis of experimental results, a modification factor for shear capacity was introduced into the existing shear capacity prediction model of strengthened brick masonry walls. The modified model exhibited good agreement with the experimental values. • Innovatively put forward GHM-strengthened method. • Influence of different factors on the mechanical property of the GHM-strengthened masonry wall is obtained. • The shear capacity calculation model for GHM-strengthened masonry wall is established.