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High-speed railway systems have begun to be widely deployed. To meet increasingly stringent requirements under harsh running environments, we propose and demonstrate three fiber-Bragg-grating (FBG)-based approaches for the strain measurement and axle counting in high-speed railway systems, including matched gratings, grating under uneven strain distribution, and semi-free grating. All approaches are laboratory verified and evaluated using the train load platform. Pros and cons are also discussed in terms of feasibility and cost-effectiveness.

Rolling-sliding wear experiments were performed to investigate the wear and rolling contact fatigue (RCF) behaviours of a premium pearlitic rail (PH), a carbon-free bainitic rail (BH) and two standard pearlitic rails (U71Mn and U75V). The wear regime and RCF damage evolution of the PH and BH materials in terms of Tγ/A (i.e. creepages and contact pressures) were compared and analyzed. The high-hardness BH steel presented a wear resistance similar to U71Mn and U75V rail materials, whereas lower wear rate was shown by the PH steel. Concerning the RCF performance, the damage of BH steel (comparable to U75V) was more severe than that of PH steel (comparable to U71Mn). Finally, with the increase in creepages and pressures, the wear and RCF damage of both PH and BH steels increased. These information could provide a guide in choosing rail materials and in development of bainitic rails.

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