Stainless steel strip – A proposed shear reinforcement for masonry wall panels

Earthquakes can cause serious damage to historic masonry structures. Masonry reinforcement has been widely studied by proposing different retrofitting methods. However it is sometimes difficult to combine the need for effective retrofitting, with high reversibility and low impact. The use of compatible-to-masonry, chemically stable and durable reinforcement materials in another difficult task. In this area, the use of stainless steel strips, as a method for reinforcing existing masonry by increasing its tensile strength and ductility, is proposed in this paper. With the aim at reproducing the in-plane seismic loading, 10 wall panels were tested in one-sense cyclic shear in the laboratory. Stainless steel strips were mechanically attached on both panel's sides using metal anchor bolts to the masonry substrate along the stretched diagonal and panel's structural response was recorded and studied. The reinforcement installation procedures, the panel's structural behavior in terms of stiffness, ductility and strength were described in detail in the paper. It is demonstrated that this retrofitting technique can enhance the mechanical behavior of the wall panels. Finally, an analysis of the features of the proposed technique indicates that it is likely to offer some advantages over some commonly-used retrofitting methods. A design procedure is also proposed and discussed in the paper.