Experimental study on physical and mechanical properties of over-wet clayey soils stabilized by calcium carbide residues

The calcium carbide residue (CCR) is utilized to improve the over-wet clayey soils, which is used as subgrade materials in highway construction. A series of laboratory tests on moisture content, particle distribution, compaction, unconfined compression strength, modulus of resilience and wetting-drying cycle are carried out to study the mechanical properties of CCR-stabilized soils and lime-stabilized soils. The binder dosages are 4%, 6%, 8%, and 4%, 6% for CCR and lime respectively. The results indicate that the CCR has higher specific surface area, pH and fine particle content. Accordingly, the CCR-stabilized soils have greater physical performance than the lime-stabilized soils in terms of particle size distribution, plasticity index, the maximum dry density and the optimum moisture content. Additionally, the mechanical performance of CCR-stabilized soils is greater than that of the lime-stabilized soils, including the unconfined compressive strength, CBR, modulus of resilience and water durability.