The over exploitation of stone quarries, the generation of construction and demolition (C&D) waste, and the steady increase in the cost of preparing additional landfill space have caused great challenges to the environment and economy. Recycled aggregate concrete (RAC), as one of
the sustainable construction material, has become a research hotspot and has received widespread attention. However, the formation of weak interface transition zone (ITZ) which caused by the existence of residual old mortar will exert a negative impact on the performance of RAC. Therefore,
various treatments have been proposed to enhance the properties of the residual old mortar, including mechanical treatment, soaking, carbonation and so on. And it has been proved that carbonation is an effective and sustainable way to both improve the water absorption of RA and strengthen
the ITZ of RAC. So, firstly, this article is devoted to reviewing the current research on the application of carbonized RA to RAC, focusing on two parts: (1) RA: the changes of physical properties under different conditions; (2) RAC: the microstructure, workability, mechanical properties and
durability of the concrete with carbonized RA. Thereafter, it is known from the summarized literatures that carbonation can improve physical properties of RA and the optimal effect can be achieved by adjusting carbonation conditions. RAC with carbonized RA has denser both new and old ITZs,
the microstructure, performance of it are also improved. Finally, this work may provide a reference for the research of carbonation and the application of RA in engineering in the future.
Influence of silica fume on mechanical and physical properties of recycled aggregate concrete