Multivariate Experimental Investigation of Impacts of Using Waste Glass on Physical and Mechanical Properties of Clayey Soil

The use of waste materials to stabilize clayey soil could be a viable solution for soil stabilization, but a comprehensive investigation is required before it can be employed. This research aims to investigate the use of waste crushed glass powder as an additive in clayey soil, providing a comprehensive overview of its impacts on the physical and mechanical properties of the soil. This is undertaken by selecting different design mix percentages of clay soil, lime, and waste glass powder. The mix design samples are tested in laboratories using the relevant American Society for Testing and Materials (ASTM) standards, and the results are then analyzed. It was found through analysis that mixing 10% waste glass powder with 5% lime into clayey soil yields the most optimum results in terms of critical mechanical properties. With this combination, the unconfined compressive strength of the soil increased from 1.86 g/cm² to 2.51 g/cm², and the shear strength of the clayey soil increased from 0.93 g/cm² to 1.26 g/cm². The California Bearing Ratio (CBR) values did not show any sign of improvement, although the permeability coefficient (k) improved from 0.000072 cm/sec to 0.000078 cm/sec. On the other hand, no substantial change in the physical properties was observed with the addition of waste glass combined with lime. This research improves our understanding of the behavior of clayey soil reinforced with crushed glass powder; benefits future civil engineers who are studying soil stabilization; provides a way to reuse waste glass and reduce its environmental impact; and helps local communities with stable and more durable structures due to improved soil conditions.