Effect of Soil Stabilization on Structural Design of Flexible Pavement

Abstract

Inadequate subgrade conditions often diminish the lifespan of pavements built on these soils. However, this challenge can be addressed through various methods, including soil stabilization, which enhances soil strength. This research focuses on soil stabilization using two types of waste materials (rubber and plastic) as additives in concentrations of 5%, 10%, and 15%, along with a consistent cement inclusion of 3% across all samples. Different tests, such as Sieve analysis, Atterberg Limits, Specific Gravity, Standard proctor Test and California Bearing Ratio, were performed for both the soil and the additive materials. As a result, this stabilization approach improved the California Bearing Ratio (CBR), leading to thinner pavement layers, which potentially lowers construction costs. Notably, the highest CBR observed was 49.95% with 10% plastic, while the top result for rubber was a 28.01% CBR at 5% inclusion. These enhancements in CBR values contributed to reducing the total thickness of the pavement layers by (435 mm) for both materials.