Experimental Behaviour of Steel-Reinforced Grout Systems Bonded to a Concrete Substrate

The behaviour of Steel-Reinforced Grout (SRG) systems bonded to a concrete substrate is experimentally investigated in this research project. Seventy-three SRG strips – or tapes - (consisting of several steel cords embedded in a layer of inorganic matrix) were bonded to as many concrete blocks thanks to the adhesion between the inorganic matrix and the concrete. The lapped joints were subsequently subjected to displacement-controlled tests in direct shear. The failure modes, the curing procedures concerning the cement-based matrix and the role played by the bonded length of the strips were among the main issues. The results show that the mechanical behaviour of the lapped joints mainly depends on the cement-based matrix, on the curing conditions and on the installation procedures, as well as on tape density (total cord area per unit width of the tape).