In the quest for sustainable and cost-effective road construction materials, a groundbreaking study led by Etienne Malbila from the Département de Génie Civil has unveiled promising results using a composite material made from lateritic soil, crushed granite, and cement. This research, published in the journal ‘Advances in Materials Science and Engineering’ (which translates to ‘Advances in Materials Science and Engineering’), could significantly impact the construction and energy sectors by providing a robust and locally sourced alternative for road pavement base layers.
The study focuses on enhancing the geotechnical properties of lateritic gravel, a material often overlooked for road construction due to its initial unsuitability. By incorporating crushed granite and varying proportions of cement, Malbila and his team created composite materials that underwent rigorous compaction and bearing tests. The results were striking. “The composite materials, particularly those with cement loadings between 1.5% and 2.5% by weight, demonstrated exceptional stability and strength, making them ideal for use as a base layer in road pavements,” Malbila explained.
One of the most compelling findings was the optimal performance of the composite material with a crushed granite loading of 30% and a cement loading of 1.5% to 2.5%. This combination yielded an optimum dry density of 2.205 tonnes per cubic meter and an optimum moisture content of 7.4%, both critical factors for road performance. The maximum bearing capacities were achieved with a cement loading of 2.5% and a crushed granite loading of 30%, with California Bearing Ratio (CBR) indexes of 410 and 548, respectively, at 95% and 98% of the optimum modified Proctor.
These results not only highlight the potential of this composite material but also underscore the importance of local resource utilization. By leveraging readily available materials like lateritic soil and crushed granite, construction projects can reduce transportation costs and environmental impact. “This research opens up new possibilities for sustainable road construction, particularly in regions where lateritic soil is abundant,” Malbila noted.
The implications for the energy sector are equally significant. Roads built with these composite materials could offer enhanced durability and reduced maintenance costs, which are crucial for the transportation of heavy machinery and materials. Additionally, the use of locally sourced materials can decrease the carbon footprint associated with long-distance transportation of construction materials.
As the construction industry continues to seek innovative and sustainable solutions, this research provides a compelling case for the adoption of composite materials made from lateritic soil, crushed granite, and cement. The findings published in ‘Advances in Materials Science and Engineering’ offer a glimpse into the future of road construction, where sustainability and performance go hand in hand. This study not only advances our understanding of material science but also paves the way for more resilient and eco-friendly infrastructure development.