Construction And Demolition Waste Used in Stabilization of Expansive Soil in Road Subgrades- A Review

Abstract- The rapid growth of construction activities has led to the generation of large quantities of construction and demolition waste (CDW), which poses serious environmental challenges due to improper disposal. At the same time, expansive soils such as black cotton soil exhibit poor engineering properties including high swelling, shrinkage, and low bearing capacity, making them unsuitable for road subgrade applications. In recent years, researchers have explored the use of CDW as a sustainable alternative for soil stabilization. This review paper presents a comprehensive analysis of previous studies on the use of CDW and other waste materials such as plastic waste, ceramic powder, and industrial by-products for stabilizing expansive soils. The findings from various studies indicate that CDW materials such as brick powder, crushed concrete, and recycled aggregates significantly improve soil properties by increasing strength, reducing plasticity, and enhancing compaction characteristics. Several studies reported improvement in California Bearing Ratio (CBR) and Unconfined Compressive Strength (UCS), making stabilized soil suitable for pavement applications [1], [12]. The review also highlights that the use of CDW reduces environmental pollution, minimizes landfill disposal, and conserves natural resources. However, variations in material properties, lack of standardized mix proportions, and limited field studies remain key challenges. Overall, the utilization of CDW in soil stabilization is an economical, eco-friendly, and sustainable approach for improving weak subgrade soils.