Characterisation and evaluation of construction and demolition waste for sustainable reuse

Recovery of inert construction and demolition (C&D) waste resources remains at a nascent stage in many developing countries, primarily due to the negative stakeholder perceptions regarding the quality of recycled aggregate (RA). This study aims to assess the potential of RA as a sustainable building material by characterising raw C&D waste through physical, chemical, mineralogical and organic content analyses, along with quality evaluation of RA in Chennai, India, as per Indian standards. The key findings include: (a) raw C&D waste contains a high proportion of bricks, mortar and fines; (b) the presence of impurities negatively affects RA quality; (c) water absorption is higher in RA compared to natural aggregates due to residual mortar, clay brick content, and microcracks; (d) water-soluble chlorides and sulphates are below 0.01%, while hazardous elements such as lead are detectable. These characteristics currently limit the uptake of RA beyond filling applications. However, by benchmarking raw C&D waste and processed RA against global and Indian standards, this study identifies multiple viable applications for both materials. It also shows that substituting natural aggregates with RA can yield cost savings of 18–50%. These findings help to expand secondary materials markets and improve recycling practices by addressing the stakeholder concerns about RA quality. This research advances SDG 11 (Sustainable Cities and Communities) and SDG 12 (Responsible Consumption and Production) by promoting circular economy.