2019 CSCE Annual Conference - Laval (Greater Montreal) Conference
Dr. Susan Tighe, CPATT - University of Waterloo
In terms of natural resources, NAs are quickly becoming exhausted worldwide due to an overwhelming demand for raw materials. Simultaneously, tremendous amounts of construction and demolition (C&D) waste are generated from various human activities including but not limited to construction, renovation and the demolition of aged buildings and civil engineering structures. To solve various problems including lowering the consumption of virgin materials, decreasing waste materials in landfills and reducing environmental problems, the utilization of recyclable waste materials, especially recycled concrete, has become a highly required and an urgent priority in the asphalt industry. This research is conducted to investigate the possibility of using coarse recycled concrete aggregate (CRCA) in asphalt mixtures by evaluating indirect tensile strength. Mix design of HMA mixtures is performed with the addition of CRCA at various percentages 0%, 15%, 30%, and 60%. After evaluation of the optimum asphalt content (OAC) of different mixtures, the indirect tensile strength of Ontario Superpave asphalt mixtures is examined. The obtained results also are statistically analyzed. The obtained results indicated that there is a considerable improvement in the tensile strength of HMA mixtures that included different CRCA proportions in both of conditioned and unconditioned status, which registered tensile strength values higher than the control mix. Additionally, differences among the results are statistically significant, indicating an increase in the CRCA proportion has a significant effect on the tensile strength of the mixture. The findings revealed that the utilization of CRCA in the asphalt mixtures appears to be highly successful.