Assessing the potential of dolomite by-products as sustainable geomaterials for road embankment applications

Dolomite by-products, often considered waste spillages from mining sedimentary rock deposits, represent a significant environmental challenge due to their improper disposal. This study investigates the potential use of these by-products as sustainable geomaterials for road embankments. Laboratory tests conducted in accordance with ASTM standards evaluated the microfabric structure, particle size distribution, compaction behavior, load-bearing capacity, and permeability characteristics of dolomite by-products. Results classify the material as well-graded silty sand with low plasticity with USCS symbol of SWSM. It falls under the AASHTO group A-1-b, indicating an excellent to good general subgrade rating. Microstructural analysis reveals angular particles with sharp edges, promoting interlocking and strength, while chemical analysis indicates a composition dominated by oxygen and carbon with traces of magnesium and calcium. The material achieves a maximum dry unit weight of 18.31 kN/m at an optimum moisture content of 8.34%, with California Bearing Ratio (CBR) values ranging from 6% to 19%, rating it as a fair subbase material. Permeability tests show medium drainage characteristics with coefficients ranging from 0.0187 cm/sec to 0.0417 cm/sec suitable for subgrade applications with adequate drainage. Predictive models for hydraulic conductivity and load-bearing capacity provide practical tools for field applications. Comparative analysis highlights the material's performance as superior to clayey subgrades and comparable to sandy subgrades. This study establishes dolomite byproducts as a viable alternative geomaterial for road construction, addressing waste disposal issues while promoting sustainable construction practices. Limitations include the absence of shear strength and compressibility data, suggesting avenues for further research.