An experimental study on the in-plane behavior of unreinforced masonry walls with an opening strengthened using steel fiber reinforced concrete overlays

Abstract

The aim of the current experimental study was to investigate the in-plane behavior of unreinforced masonry (URM) walls with an opening retrofitted using steel fiber reinforced concrete (SFRC) overlays on both faces. For this purpose, four large-scale walls retrofitted with different retrofitting schemes were tested under simultaneous gravity and in-plane lateral loads. The test specimens included a reference URM wall, a wall retrofitted completely using a two-sided SFRC overlay, and two walls with retrofitted piers or spandrels. The SFRC mix proportions and thicknesses were the same in the test specimens. The results of the experimental study indicated that adding the SFRC overlay to the whole surface of the walls with an opening not only led to a significant enhancement of the in-plane strength and stiffness of the walls, but also improved their nonlinear deformation capacity. Consequently, it can be used as an efficient retrofitting technique for URM walls. Additionally, the test results indicated that retrofitting the piers of a wall with an opening can also considerably improve its in-plane behavior in terms of strength, stiffness, and deformation capacity. However, strengthening the spandrels had a relatively minor contribution to the enhancement of the in-plane behavior of the walls with an opening.