Addressing performance and environmental challenges with using Crumb Rubber Asphalt for NT roads

The project aims to address the lack of research on the use of recycled tyre products, specifically tyre crumb, in asphalt mixtures under the harsh weather conditions of the Northern Territory (NT). While studies on the use of crumb rubber in asphalt exist in other states of Australia, these regions experience more moderate weather conditions compared to the extreme heat, UV exposure, and temperature fluctuations found in the NT. This surprising lack of available research evidence has led to uncertainty among industry stakeholders and government bodies about adopting crumb rubber in road pavements within the NT. The primary objective of this research is to conduct a comprehensive mechanical and performance evaluation of various asphalt mixtures incorporating recycled tyre crumb. These mixtures will be tested for their resistance to key structural distresses of asphalt pavements, including fatigue cracking and rutting, as well as aging, particularly under the high UV exposure and intense heat characteristic of the NT climate. By focusing on these critical performance factors, the project will determine how crumb rubber can enhance pavement durability in such demanding conditions. In addition to the mechanical assessments, the project will carry out a detailed environmental evaluation to ensure that the use of crumb rubber in asphalt poses no significant risks. This includes analyzing potential leachate or other environmental impacts of using recycled tyre material in road construction. The ultimate goal is to ensure that the asphalt mixtures not only meet performance standards but also align with environmental regulations and sustainability goals. A key outcome of this project will be the development of a prototype asphalt mixture optimized for the unique conditions of the NT. This mixture will maximize the content of crumb rubber while ensuring it performs comparable or superior to the conventional asphalt mixtures under the region's extreme weather and meets environmental safety standards. Industry partners will play a critical role in shaping this outcome, providing insights and significant contributions by providing access to their facilities to ensure the mixture's feasibility for large-scale application. Upon successful completion of the performance and environmental assessments, the project will move toward field trials and commercialization of the optimum asphalt mixture. These trials will provide further validation of the mixture's effectiveness in real-world conditions. Based on the findings, recommendations will be made to the NT road authorities to revise current standards and specifications, paving the way for the formal introduction of crumb rubber as a sustainable pavement material. Such changes would encourage contractors and asphalt producers to adopt crumb rubber, promoting the use of recycled materials in road construction. This project aligns with broader sustainability goals, particularly the aim to achieve net-zero emissions and conserve natural resources. By utilizing waste products from used tyres, this initiative contributes to reducing landfill waste, conserving raw materials, and creating more durable and environmentally friendly road pavements.