Mechanical behavior and failure modes of two different steel-FRCM systems on masonry substrate: Experimental investigation

The paper presents the results of single-lap shear tests carried out on specimens with Steel Fabric Reinforced Cementitious Matrix (S-FRCM) composite strips bonded to masonry units. The S-FRCM composite system represents a newly developed promising technique for strengthening the masonry structures. The S-FRCM composite was comprised of steel fiber strip embedded within two layers of inorganic matrix. Two kinds of steel fibers can be used: ultra-high tensile strength steel galvanized micro-cords and/or stainless steel strands. The main differences between the two fibers are: E modulus with a ratio of 2.58 and tensile strength with a ratio of 2.04. This experimental investigation was carried out in order to obtain information on the fundamental behavior of the bond between masonry and the two types of S-FRCM composites, which is the critical phenomenon in structural strengthening applications due to a slip of the fibers and fracture of the external matrix layer at the fiber-matrix interface. The results were analyzed and showed in terms of failure modes, failure loads, load-global slip curves, and other parameters.