Short- and long-term properties of self-compacting concrete containing recycled coarse aggregate under different curing temperatures: experimental and numerical study

The present experimental and numerical study investigates the impact of coarse recycled concrete aggregate (CRCA) on the short and long-term properties of self-compacting concrete (SCC) subjected to different curing temperatures. In addition, finite element analysis (FEA) was utilized to estimate the total shrinkage of the SCC. Three CRCA replacement ratios (0%, 50%, and 100%) and three temperatures (20 °C, 35 °C and 50 °C) were chosen as the two main parameters. The results reveal that the mechanical performance of SCC mixes generally weakened with increased CRCA replacement ratio. The reductions were 11%, 13% and 7% as compared to the control mix, for the compressive strength (fc), modulus of rupture (Mr) and elastic modulus (Ec), respectively, when a 50% CRCA replacement ratio was used. Furthermore, the total shrinkage of SCC mixes increases considerably both with increases in curing temperature and in CRCA percentage. For the same room temperature (20 °C), the total shrinkage increased by 20% and 60%, corresponding to the addition of 50% and 100% of CRCA, while for the SCC mixtures subjected to a temperature of 50 °C, the increases were 23% and 14%, respectively. Finally, the total shrinkage results obtained by the FEA are very close to the measured values. It is recommended to use 50% and 100% CRCA for manufacturing new SSC mixture, which seems to be a high-appropriate solution.