Date of Award
2024
Document Type
Thesis
Publisher
Edith Cowan University
Degree Name
Master of Engineering Science
School
School of Engineering
First Supervisor
Associate Professor Sanjay Shukla
Abstract
The mining industry creates a huge amount of waste products, known as the mine tailings. Their handling and disposal have been challenging tasks, and moreover, they seriously affect surrounding environment and human health. Australia's road system is indeed one of the largest road systems in the world. It uses a lot of natural resources in its construction and maintenance operations. As per the current construction practice requirements, it is essentially required to reduce use of conventional materials in view of protecting environment, preserving natural resources and reducing carbon footprint. To find sustainable and economical solutions, this research examines the utilization of mine tailings in construction of pavement. This will not only reduce the negative impacts of mining industry on environment but also have tremendous potential to replace conventional materials in the construction of pavement.
This study focuses on the key objective by utilizing mine tailings for flexible pavement construction. Following the AASHTO Guide (1993), the study meticulously designs flexible pavements for diverse vehicles and axle weights. This study has investigated the California Bearing Ratio (CBR) values of six samples incorporating distinct proportions of clay soil and mine tailings for the design of flexible pavement using the 1993 AASHTO design guide. Through systematic approaches, including an equation solver calculator, the study determines layer thicknesses required to achieve the desired Structural Number (SN) for optimal pavement structural integrity. The analysis revealed that the sample with 20% clay and 80% mine tailings exhibits the highest CBR values, making it a promising choice for flexible pavement construction. Specifically, this composition results in a CBR of 17.35 % and Modulus of Resilience (MR) of 51900 lb/in2, leading to a negative depth for the base course layer. The negative depth suggests an opportunity to optimize pavement design by potentially reducing or eliminating certain layers, leveraging the robust nature of the subgrade with a high modulus. Overall, the study underscores the potential for cost-effective and efficient pavement design iv optimizations based on specific soil compositions, providing excellent load-bearing capacity for flexible pavement construction.
Extending its focus to Life-Cycle Assessment (LCA), this study comprehensively evaluates the environmental impact of pavement construction. A case study has been conducted to compare the life-cycle assessment of conventional materials with that of mine tailings, upon comprehensive analysis, both conventional and mine tailings pavements exhibit relatively similar Global Warming Potential values. Notably, the mine tailings pavement presents an overall lower cumulative energy consumption, attributed to reduced energy requirements during manufacturing and construction phases. This finding underscores the potential environmental advantages of mine tailings, particularly in mitigating the impact of raw material extraction and enhancing end-of-life sustainability through higher recycling quantities.
In conclusion, this research not only proposes a sustainable and economical solution for pavement construction but also contributes valuable insights for geotechnical engineers. By showcasing the potential of mine tailings, the study advances environmentally friendly practices in geotechnical engineering, aligning with sustainability goals and offering a promising avenue for future pavement construction.
DOI
10.25958/a65d-zv07
Access Note
Access to this thesis is embargoed until 6 June 2029
Recommended Citation
Sheth, K. P. (2024). Utilization of mine tailings in construction of pavement. Edith Cowan University. https://doi.org/10.25958/a65d-zv07