Performance Evaluation of Construction and Demolished Waste in Stone Mastic Asphalt Mixtures

The population growth in Kingdom of Saudi Arabia has increased the demand for expansion in housing and infrastructure inventory unavoidably resulting in huge accumulation of construction and demolition waste (CDW). An estimated 50 million tons of CDW are generated annually, making it almost half the municipal solid waste. Expectedly it will go further high with the ongoing construction projects. This creates potential for the utilization of sound waste management practices to implement. This research study explored the potential use of demolished concrete waste in asphalt concrete layer. This will help in preservation of the non-renewable resources, waste management and most importantly to achieve grand national objective i.e., recycling/reusing up to 2035. For achieving the desired results, detailed laboratory performance testing using Superpave mix design method has been done for the optimal utilization of CDW in stone mastic asphalt mixtures. Different percentages of CDW (5, 10, 20, 30 and 40) % have been used as trials in the mixes to obtain the best mixture performance. Using wet/dry Indirect Tensile Strength (ITS), moisture susceptibility was investigated. The results shown in the current study indicated that the CDW aggregate utilization in mixtures has shown good performance in moisture resistance and enhanced resistance values as compared to the conventional mixture. The SMA mixes engineering properties containing the low percentages of CDW showed acceptable trends and satisfied the design standard requirements.