Evaluation of bond strength and direct tensile strength of geopolymer mortar with concrete substrate using pull-off tests

Abstract

In order to assess the dependability of externally reinforced concrete buildings, one must be familiar with the long-term performance of the interfacial transition zone (ITZ) between adhesive materials and the concrete substrate. Use sustainable geopolymer binders to enhance the mechanical capabilities and longevity of concrete components during strengthening and repair processes. In this investigation, the adhesive-to-concrete substrate binding strength was measured using a computerized pull-off strength tester (E142) in line with standard testing procedures. In place of epoxy, this study presents the findings and analysis of a pull-off test that used geopolymer mortar (GPM). Experimental and measurable data included failure mechanisms, bond strength, energy-dispersive X-ray spectroscopy, and scanning electron microscopy (SEM). The fact that the concrete substrate finally collapsed on all connected surfaces shows how strongly the geopolymer mortar adhered to the concrete. Therefore, GPM shows promise as an eco-friendly and cost-effective substitute for epoxy in rehabilitation and repair applications, which might help concrete buildings last longer and be more sustainable. Substrate failure, adhesive failure, and cohesive failure were the three bonding failure mechanisms that were studied in each test.