Investigation on properties of coarse reclaimed aggregates and their effects on concrete strength and workability

Fresh concrete waste is constantly generated in concrete batch plants during the production of ready‐mix concrete, and this waste is generally dumped in landfills. Natural aggregates are a finite resource and therefore there is a need to recycle this fresh concrete waste. An on‐site reclaimer can recycle fresh concrete waste to produce reclaimed aggregate (RA) and eliminate the need to dump fresh concrete waste in landfills. This study investigates the properties of coarse RAs sampled from an Australian concrete batch plant. It was observed that the particle size distribution was highly varied, while particle density and water absorption were similar to their parent aggregate. It was also found that concrete containing coarse RAs exhibited a higher workability and lower compressive strength than concrete containing natural coarse aggregates. Utilization of coarse RAs in concrete application is a viable option; however, more research will need to be conducted in this area.