The rapid growth of construction activities in India has led to a significant increase in the generation of construction and demolition waste (CDW). This waste poses a major environmental and economic challenge. One sustainable method to manage construction and demolition waste is to reuse the aggregates that are collected after the demolition of structures and damaged roads. In this study, a design mix of granular sub base (GSB) layer of close graded-grading II was considered. The GSB layer is a layer of compacted aggregate that is placed below the road surface to provide a stable base for the pavement. The design mix consisted of 40, 20, and 10 mm natural aggregates (NA), 20 mm of recycled aggregates (RA) collected from demolished buildings/concrete waste/damaged roads, and blended soil (BS). The properties of the clay with intermediate plasticity soil were enhanced with the addition of crusher dust for the preparation of BS. The RA were used to replace the NA in the design mix. The best combination of aggregates that met the specifications of the Ministry of Road Transport and Highways was selected. The results showed that up to 60% of the 20 mm natural aggregates could be replaced with recycled aggregates without compromising the performance of the GSB layer. The maximum dry density and optimum moisture content after replacement were found to be 2.00 g/cm3 and 10.37%, respectively. The California Bearing Ratio value at 2.5 mm penetration was also found to be 38.47. These results suggest that RA can be used as a sustainable alternative to NA in the construction of GSB layers. This can help to reduce the environmental issues of CDW and save natural resources.
