Synergistic effects of steam curing and recycled concrete powder on the mechanical performance of eco-concrete made with recycled concrete aggregates

This study investigates the synergistic effects of recycled concrete powder (RCP) and steam curing on the properties of eco-concrete incorporating 50% recycled concrete aggregates (RCA). The goal is to determine the optimal RCP dosage and the most effective curing method. Portland cement was partially substituted with RCP at replacement levels of 10%, 20%, and 30%, and the impact on workability and compressive strength was evaluated under two curing regimes: water curing at 20 ± 1 °C and steam curing at 50 °C. The results indicate that 10% RCP improves workability by 53.4%, while higher replacement levels decrease is due to the increased water absorption capacity of RCP. Steam curing accelerates early-age strength development by activating the pozzolanic potential of RCP; however, excessive RCP content may compromise long-term strength when exposed to elevated curing temperatures. This study highlights a viable approach for incorporating recycled materials in concrete, contributing to sustainable construction practices by reducing cement consumption and promoting waste valorization.