An architecture of lifecycle fatigue management of steel bridges driven by Digital Twin

The fatigue of steel bridges poses a great threat to their safety and functionality. However, current approaches for fatigue management are largely based on heuristic design philosophies, physical testing, and bridge managers' experience. This paper proposes a closed lifecycle fatigue management driven by Digital Twin for steel bridges. To provide clarity around the concept, the definition of Digital Twin for steel bridges is given at first. Then eight functional modules supporting Digital Twin are outlined in detail, aiming to provide a reference for the future development of Digital Twin in fatigue management. Finally, the implementation mechanism of Digital Twin is further described over different phases during the bridge lifecycle. This paper also identifies two main obstacles for the development of Digital Twin: i) the lack of understanding of steel bridge fatigue, and ii) the insufficiency of the present technologies.