School of Civil Engineering, Iran University of Science and Technology (IUST)
Post-doctoral researcher, Iran university of Science and Technology
This study aims to investigate the effects of key parameters on the interfacial bond strength between two concrete members. Different types of overlay in terms of strength, surface roughness, and adhesive type were considered as variable factors influencing the bond behavior. First, the surface roughness of the old concrete and the compressive strength of the concrete overlay were evaluated separately, and then among the specimens, the composite with the highest bond strength was chosen as the optimum concrete composite. Afterwards, epoxy adhesive and cellulose mortar were applied to the optimum sample, and its corresponding interfacial strength was evaluated by bi-surface shear and splitting tensile strength tests. The results showed that, as the compressive strength of new concrete and concrete roughness increase, the bond strength increases. Moreover, the interfacial bond strength of composite with the wire-brushed surface was the highest among other treatment methods, due to the interlocking action it provides. The bond strength of concrete composites containing epoxy adhesive was ∼100-200% higher than that of samples without epoxy resin. Therefore, it is anticipated that the use of high-strength concrete concomitant with wire-brushed surface treatment and epoxy resin adhesive shows substantial potential as an excellent method for repair of concrete structure.