Stabilization of expansive soil using different combinations of glass powder and rice husk ash

The global issue of expansive soil is the root cause of significant harm to structures designed for civil engineering. The difficulty with expansive soils is that they expand when water is absorbed and contract when it evaporates because of clay minerals including kaolinite, montmorillonite. Because of its poor shear resistance and load-bearing capacity, it makes it difficult to build foundations for Infra Construct. The expansive soil is widely distributed worldwide, especially in certain regions of Pakistan including Sindh, Punjab, and KPK. The soil was gathered for this study from Kohat KPK's Shindand region. For such soils to be acceptable for construction, they must be stabilized. The soil was stabilized using different combinations of leftover glass powder and rice husk ash (RHA). Expansive soil samples mixed with various combinations of Glass Powder and Rice Husk Ash (RHA) were subjected to various geotechnical tests, including Sieve Analysis, Hydrometer analysis, Atterberg limit, Free Swell Index (FSI), Standard Proctor Test (SPT), Unconfined Compression Strength (UCS), and California Bearing Ratio (CBR). According to Atterberg's limit, adding 3% GP and 6% RHA results in a significant reduction of the Liquid Limit (LL), Plastic Limit (PL), and Plasticity Index (PI), providing the ideal dose level. Additionally, adding 3% GP and 6% RHA resulted in a drop of 10.8% in the optimal moisture content (OMC) and an increase of 1.42% in the treated soil's maximum dry density (MDD). Adding 3% GP and 6% RHA reduces the Free Swell index by 27.2%. After treating the untreated soils with 3% GP and 6% RHA, the UCS significantly increased by 160.6%.