Most modern railways use continuous welded rail (CWR) because they support higher transport speeds, provide less friction, and generally require less maintenance. However, thermal buckling of CWR has been a long-standing challenge for the railroad industry. Rail neutral temperature (RNT) is the temperature at which the longitudinal stress of a rail is zero. Due to the lack of expansion joints, CWR develops internal tensile or compressive stresses when the rail temperature is below or above, respectively, the RNT. Therefore, thermal stress or RNT measurement and management of CWR become more important for railroad maintenance. In this work, the team proposes a practical and nondestructive method for RNT estimation exploiting local resonances in rails.
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