Structural engineering applications of recycled aggregate concrete: Seismic performance, guidelines, projects and demonstrations

In this paper, the most-concerned questions of recycled aggregate concrete (RAC) application, i.e., the structural safety performance, the availability of design code and project experience, and ecological and economic costs, are overviewed, aiming to find the answer to whether it is feasible to apply RAC in main structural components technically and practically. Firstly, RAC structural performances were analyzed. The failure pattern, load-carrying capacity, energy dissipation capacity, and ductility of the RAC structures were compared with those of natural aggregate concrete (NAC). The results confirm the safety of the RAC structures in most scenarios. Secondly, the specifications and standards for RAC structures of different countries, the attitude of engineering participants, the optimum preparation methods of recycled aggregates, and the projects using RAC are reviewed. Finally, the ecological and economic benefits of applying RAC to replace NAC in structures are investigated, showing a reduction in the projects' overall cost and promotion of social advantages due to its sustainable, low-carbon, and resource-efficient features. The authors hope that this research will serve as a stimulus to promote the applications of RAC in structural engineering and address the problems posed by C&D waste and the scarcity of natural aggregates.