Review Paper on Performance Evaluation of Flexible Pavement on Different Subgrades with Industrial Waste

The design of flexible pavements heavily relies on the behavior of the subgrade, which serves as the foundation for the entire pavement structure. Therefore, careful attention must be given to both the performance and design analysis during pavement construction. Expansive soils, which contain high percentages of silt and clay, require stabilization or compaction before laying the pavement. Stabilizing these soils can be achieved by replacing the subgrade with alternative materials. Fly ash, an industrial waste with a current utilization rate of about 55%, presents an opportunity for such stabilization. By replacing a portion of the subgrade with fly ash and reinforcing it using bitumen-coated chicken mesh at varying percentages and layer placements, the stability of the pavement can be enhanced. This reinforcement has been shown to significantly improve the California Bearing Ratio (CBR), with maximum strength achieved when 15% of the soil is replaced with fly ash and four layers of bitumen-coated chicken mesh are used.