Current progress on nanotechnology application in recycled aggregate concrete

As a very promising sustainable construction material, recycled aggregate concrete (RAC) has become a hot research topic and attracted wide attention. Although many investigations have been conducted, it is still a great challenge to product RAC with satisfactory and stable performance for practical engineering application. In recent years, nanotechnology has been introduced to RAC research and displayed distinct advantages over many traditional methods. This article is devoted to reviewing the current research on nanotechnology application in RAC, including nanoengineering and nanoscience. The corresponding results involving microstructure characteristics, mechanical properties, workability, and durability were summarized and discussed. It has been found that nanoscience has promoted better understanding of microstructure and various internal mechanism of RAC, while nanoengineering has helped RAC achieve dense microstructure, improved mechanical properties and durability. However, further efforts are required to realize the potential of nanotechnology and to bring breakthroughs in research and application of RAC.