Performance assessment of recycled aggregates from C&DW plants for road embankments: Influence of composition and treatment methods

Construction and Demolition Waste (C&DW) represents a promising alternative to natural aggregates in the road construction sector. However, the viability of recycled aggregates (RAs) depends on fitting technical requirements set by construction standards. This case study investigates RAs produced by three operational C&DW treatment plants in Northern Italy, focusing on their physical and mechanical properties and compliance with technical documents UNI 11531-1 and Circular no 5205 for road embankment use. A total of 10 representative RAs samples were analyzed for particle size distribution, shape, flakiness, plasticity, and abrasion resistance. Results show significant differences related to the type of treatment methods and C&DW initial composition, with a clear impact on the performance by technical specifications. The study identifies operational parameters that influence RAs quality and provides engineering recommendations to improve compliance, including blending strategies and selective demolition practices. These findings contribute to enhancing C&DW valorization in roadworks and protection embankments, supporting the transition toward circular and low-impact infrastructure materials. Moreover, the compliance-based assessment framework adopted in this study is applicable beyond the Italian context, offering a transferable methodology for evaluating recycled aggregates under different national or regional technical standards.