FLEXIBLE PAVEMENT DESIGN USING INDUSTRIAL WASTE FOR SUBGRADE SOIL STABILIZATION

Abstract

The project “Flexible Pavement Design Using Industrial Waste for Subgrade Soil Stabilization” focuses on improving the engineering properties of weak subgrade soil by utilizing suitable industrial waste materials. The strength and stability of subgrade soil play an important role in the performance and service life of flexible pavements. Weak or expansive soils may undergo excessive deformation under repeated traffic loading, resulting in pavement failures such as rutting, cracking, and uneven settlement. Therefore, stabilization of weak subgrade soil is necessary to improve its load-bearing capacity and reduce pavement deterioration. The study investigates the use of selected industrial waste materials as stabilizing agents for subgrade soil. Materials such as fly ash, steel slag, cement kiln dust, or other suitable industrial by-products can be incorporated into the soil in different proportions. Laboratory tests are conducted on untreated and stabilized soil to evaluate properties such as moisture content, specific gravity, Atterberg limits, compaction characteristics, and California Bearing Ratio (CBR). The results are compared to determine the improvement achieved through stabilization. The stabilized soil is then considered for flexible pavement design based on the improved subgrade strength. Different percentages of industrial waste can be evaluated to identify an optimum content that provides adequate strength and stability. The improved CBR value can be used as an important input for determining suitable pavement layer thickness. This approach can reduce the requirement for conventional soil improvement materials while providing a useful application for industrial waste. Overall, the project demonstrates the potential of industrial waste-based soil stabilization as a sustainable approach to flexible pavement construction. The study aims to improve subgrade performance, reduce pavement thickness where technically appropriate, and promote the beneficial reuse of industrial by-products. The proposed approach provides an economical and environmentally responsible solution for developing durable flexible pavements over weak subgrade soils.