Mechanical characteristics analysis of the orthotropic steel deck in heavy-haul railway bridges

This paper aims to assess the mechanical characteristics of the orthotropic steel deck (OSD) in heavy-haul railway bridges. Taking the Dongting Lake Bridge as an example, to simulate the transfer effect of the track structure and get mechanical characteristics of the OSD under the service load, the refined segmental finite element model (FEM) of the OSD in a heavy-haul railway bridge was established. Moreover, the Chinese C-80 heavy-haul train (the C-80) was selected as the applied load to make the analysis results close to the actual situation. And then, the stress influence lines of critical components in OSD were analyzed. Notches at diaphragms of the OSD are more likely to produce stress concentration. Due to the dense distribution and high stiffness of the longitudinal ribs of OSD, the final load influence range of OSD is limited. Since the T-shaped longitudinal ribs (T-Ribs) are located under the position of each rail, and its stiffness is greater than the adjacent U-shaped longitudinal ribs (U-Ribs), so that the T-Ribs are important load-bearing components of the OSD in heavy-haul railway bridges. Furthermore, the influences of the stiffness ratio of T-Rib to U-Rib on the mechanical characteristics of the OSD were analyzed.