In the quest for sustainable construction materials, researchers have turned to industrial byproducts to tackle a longstanding challenge in geotechnical engineering: stabilizing high plasticity soils. A recent study published in the journal *Discover Materials* (translated from Russian as “Find Materials”) explores the potential of marble dust and molasses to transform expansive soils, offering promising implications for the energy sector and beyond.
Expansive soils, known for their poor mechanical properties and significant swelling and shrinkage behavior, pose substantial challenges in construction. These soils often lead to structural damage and increased maintenance costs, particularly in infrastructure projects. The study, led by Abhishek Sharma from the University Centre for Research and Development at Chandigarh University, investigates the use of marble dust (MD) and molasses (M) as eco-friendly stabilizers for these problematic soils.
The research team conducted a series of laboratory tests to assess the impact of varying percentages of marble dust and molasses on the geotechnical properties of expansive soil. Key tests included differential free swell, Atterberg limits, modified Proctor test, unconfined compressive strength, California bearing ratio (CBR), pH, and electric conductivity.
The results were striking. The addition of marble dust and molasses significantly reduced the differential free swell, liquid limit, and plasticity index of the soil. Notably, a combination of 15% marble dust and 6% molasses nearly eliminated the soil’s swelling potential and transformed it from high to low plasticity, making it suitable for subgrade applications.
“This combination not only improved the soil’s mechanical properties but also enhanced its density and strength,” said Sharma. “The maximum dry density reached 1.922 g/cc at an optimum moisture content of 10.6%, and the unconfined compressive strength increased by 124% after 28 days.”
The study also revealed that the soaked California Bearing Ratio (CBR) for the optimized mixture of soil, marble dust, and molasses was 15.28%, indicating a substantial improvement in load-bearing capacity. Scanning Electron Microscopy (SEM) analysis further showed that marble dust densified the soil structure, while molasses improved particle bonding. Additionally, the pH and electrical conductivity tests indicated that marble dust increased soil alkalinity, which was balanced by the acidity of molasses.
The implications of this research are far-reaching, particularly for the energy sector. Expansive soils are common in many regions where energy infrastructure, such as pipelines and power plants, is developed. Stabilizing these soils can reduce construction costs, enhance the longevity of structures, and minimize environmental impact.
“This research opens up new possibilities for using industrial byproducts in construction,” said Sharma. “By leveraging materials like marble dust and molasses, we can create more sustainable and cost-effective solutions for stabilizing soils, which is crucial for the energy sector and other industries.”
The study, published in *Discover Materials*, highlights the potential of innovative, eco-friendly approaches to geotechnical challenges. As the demand for sustainable construction materials continues to grow, the findings of this research could shape future developments in soil stabilization, offering a blueprint for more resilient and environmentally friendly infrastructure.