Prediction of the mechanical behavior of recycled concrete with fresh concrete waste aggregate

Abstract

AbstractCrushing fresh waste concrete that collects from ready‐mixed concrete plants to prepare aggregates for new concrete production reduces the carbon dioxide footprint. This study intends to predict the mechanical properties of recycled concrete with fresh concrete waste aggregate (FCWA), including compressive strength development over time, elastic modulus, and shrinkage. Current available experimental studies were first summarized to investigate the impact of FCWA incorporation on the mechanical properties of resulting concrete. Prediction expressions were proposed for compressive strength development over time for recycled concrete accounting for FCWA replacement (r) ratio. Elastic modulus and shrinkage prediction models were theoretically derived for recycled concrete accounting for the residual cement paste content (CRCP) of FCWA and benchmarked against available experimental results. Results showed that concrete decreased its mechanical properties with increasing FCWA r ratio. 35.7‐58.7% reductions in the compressive strength and 36–55% reductions in the elastic modulus for FCWA concrete could be observed, while 66–108% increases in the shrinkage could be obtained for concrete with FCWA r ratio of 30%. The models proposed in this study well predicted the mechanical properties for FCWA concrete.