Enhancing mechanical performance of waste tire concrete with surface double pre-coating by resin and micro-silica

Abstract

The use of Waste Tire Crumb Rubber (WTCR) instead of aggregates in cement-based concretes has been expanded to produce more sustainable, lighter, and ductile concrete with more damping. However, it creates weaknesses in the mechanical properties of concrete, such as compressive and flexural strength. This study proposes an innovative surface double pre-coating with resin and micro-silica to improve the bond at the Interfacial Transition Zone (ITZ) between WTCR and cement paste. The WTCR replaced natural fine aggregates by volume ranging from 0% to 30%. The scanning electron microscopy images are used to investigate the changes in the created gaps and micro-cracks in ITZ. The modified rubber concrete's compressive, modulus of elasticity, and flexural strength are improved by using double pre-coated rubber methods up to 60%, 28%, and 30%, respectively. Also, the ultimate strain capacity is still more than the ultimate strain capacity of ordinary concrete. The results show that the double-pre-coating resin and micro-silica methods have the maximum effect in increasing the concrete samples' mechanical performance.