ABSTRACT
The durability and resilience of reinforced concrete (RC) structures are significantly compromised by various environmental-assisted degradation processes, including chloride ingress, rebar corrosion, and fire damage. These processes inherently exhibit a multi-physics field and multi-scale nature. This paper demonstrates a multi-physics field and multi-scale predictive theory for RC structures, with a particular focus on degradation caused by rebar corrosion and fire induced degradation. The hierarchical concept of RC components at different scales is first introduced, followed by a detailed review of aggregate modeling, collision detection, and packing algorithms for constructing meso-scale models of concrete. Comparative analysis of these methods is provided. The multi-scale method based on the homogenization approach is demonstrated using chloride transport as an example. Next, the significance of multi-physics field computations in understanding degradation mechanics of RC structures is emphasized. Computational strategies addressing concrete degradation processes induced by rebar corrosion and fire attack are proposed. The obtained damage processes in concrete are shown to agree well with experimental results. Finally, the challenges and prospects of current research are discussed, focusing on multi-scale refined modeling, coupling mechanisms for multi-physics fields, and efficient intelligent computational frameworks. This review highlights the potential of integrating multi-scale and multi-physics methods to enhance understanding and improve RC structures under complex environmental conditions.
