Bond Strength Evaluation of Polymer Modified Cement Mortar Incorporated with Polypropylene Fibers

Bond strength is the adhesion between an overlay and a substrate mortar, it is the key parameter ensuring the durability and having a monolithic system. A proper bond is essential to resist any stresses at the interface associated with volume-changes, freeze-thaw cycles, and vibrations, etc. Polymer-modified cement mortar (PCM) is one of the most well-known adhesive materials, used widely as a binding agent in the engineering construction. Two forms of PCM were investigated in this study. These products are known commercially as Sika MonoTop®-620, which is a form of repair material for concrete structures, and DCP Cemfix 2CS, which is occasionally used as an adhesive to connect the tiles to the concrete base. The effect of polypropylene fiber with volume fractions of 0, 0.5, 0.75, and 1 percent was investigated using three different water-to-binder ratios. A total of 24 distinct mixes were made. The compressive strength, flexural strength and bond strength of the materials were all determined. The bond strength of each mix was assessed using the Slant-Shear and Pull-off test methods. The bond strength values derived by Slant-Shear and Pull-off tests had a high correlation, it was about 85%. Furthermore, bond strength was connected with the material's compressive and flexural strength with a relation of 95% and 86% with Slant-Shear, also 80% and 76% with Pull-off, respectively.