Development of Constitutive Model for Tie-Confined Recycled Aggregate-Based Self-Cured SCC Under Axial Compression

This study examines the stress–strain behaviour of self-curing self-compacting concrete (SCC) containing 100% recycled aggregates within the mix. The findings emphasize the dual functionality of recycled aggregates, which act not only as structural components but also as internal curing agents when combined with self-curing compounds like polyethylene glycol. This combination facilitates the release of supplementary water, ensuring continuous hydration throughout the concrete matrix. A new nondimensional stress–strain equation for tie-confined SCC with recycled aggregates is introduced, accounting for varying curing conditions. Comparative analysis with existing confined concrete models reveals that the models by Belen et al. and Chen et al. demonstrate strong alignment with the experimental findings. This research underscores the potential of recycled aggregates to not only enhance sustainability but also improve the mechanical performance of concrete, offering a viable, eco-friendly solution for modern structural applications.