GEOTECHNICAL PROPERTIES OF EXPANSIVEV SOIL STABILIZED WITH CEMENT

This study investigates the effect of cement stabilization on the engineering properties of an expansive soil with the aim of improving its suitability for construction purposes. Expansive soils often exhibit low strength, high compressibility, and inadequate load-bearing capacity, making them unsuitable for pavement subgrades and other engineering works. To enhance the performance of the soil, Ordinary Portland Cement (OPC) was added in varying proportions of 2%, 4%, 6%, 8% and 10% by dry weight of soil. Laboratory tests including Atterberg limits, grain size distribution, Standard Proctor compaction and California Bearing Ratio (CBR) were conducted on both natural and stabilized soil samples. The natural soil exhibited low plasticity with a plasticity index of 2.84% and a very low CBR value, indicating poor strength characteristics. The addition of cement significantly improved the soil properties. The Maximum Dry Density (MDD) increased steadily with cement content and reached its peak at 8%, showing improved soil structure and better compaction characteristics. The CBR values increased progressively from 6.4% in the natural soil to 66.05% at 10% cement, demonstrating a major improvement in the load-bearing capacity of the stabilized soil. The increase in strength is attributed to the formation of cementitious bonds which enhance particle interlocking and overall soil rigidity. The results confirm that cement is highly effective in improving the engineering behavior of expansive soil. The stabilized soil achieved adequate strength and density to meet the requirements for pavement subgrade and other structural applications. The findings show that cement stabilization transforms a weak soil into a more durable and stronger material, suitable for use in geotechnical and highway engineering projects.