Valorization potential of post-earthquake controlled demolition waste for circular construction materials: Field-laboratory assessment of recycled aggregates in Türkiye

This study evaluates the valorization potential of recycled concrete aggregates (RCAs) and recycled mixed aggregates (RMAs) obtained from post-earthquake controlled demolition waste (DW) in Türkiye for use in road construction, concrete production, and cement manufacturing. The samples were collected from controlled demolition of buildings constructed in different periods, reflecting revisions of the Turkish Seismic Codes, as well as from a Temporary Storage Site (TSS) representing mixed debris. A comprehensive experimental program was conducted to assess the physical, mechanical, durability-related, and chemical properties of the recycled aggregates (RA). The findings reveal relationship between building construction age and RA quality. RCAs derived from buildings showed better performance; higher density, lower water absorption, improved abrasion, freeze–thaw resistance, and lower chemical reactivity, making it more suitable for road base and subbase layers as well as for concrete and cement production than RMA. In contrast, RMA showed limited applicability due to its heterogeneous composition. The variability of DW samples obtained from a TSS underscores the importance of source-based separation to maintain RA quality. Overall, the study establishes a scientific framework by demonstrating how seismic-code-oriented building classifications serve as a primary indicator for the valorization potential of DW. This approach moves beyond generic building age, providing a predictive methodology for identifying high-quality secondary resources in disaster-prone regions, thereby supporting targeted circularity in structural materials.