Mechanical characterization of steel-reinforced grout for strengthening of existing masonry and concrete structures

Steel-reinforced grout (SRG) materials are thin laminates made of continuous fabrics of high-strength steel cords embedded within a cementitious matrix. This paper investigates the mechanical characterization of four SRG systems used to strengthen masonry and concrete structures. Characterization tests were conducted in accordance with current standards. The SRG systems investigated in this study were composed of two types of steel textiles of different mass density, combined with two different types of mortar (a cement-based and a hydraulic lime-based mortar). A total of 95 SRG specimens were manufactured to carry out tensile (80 specimens) and interlaminar shear (15 specimens) tests. In addition, 70 pull-off bond tests were executed on several substrates (clay brick, concrete masonry, and cementitious masonry units). Moreover, compression tests on 40 mortar cubes were conducted to determine the strength of the matrices at 3, 7, 14, and 28 days of curing. The test results are presented and discussed clearly identifying the mechanical parameters of SRG composites.