Measurement of Longitudinal Stress in Railroad Rail Under Field Conditions Using Nonlinear Harmonics
Track buckling in continuously welded rail is a significant problem in the railroad industry [1–3]. Buckling is caused by the buildup of compressive stress (longitudinal force), which is primarily caused by an increase in rail temperature while the rail is constrained and cannot expand longitudinally. The buckling is typically manifested in the wavy lateral displacement of the track over a distance of approximately 100 feet . Because buckling can cause the derailment of a passing train, extensive efforts are spent on preventive maintenance of the track. If a region of rail is known to be in a high state of compressive stress, the rail can be de-stressed by cutting it, allowing it to expand, and then welding it back together. Currently, one of the major difficulties in preventing track buckling is lack of a means for detecting the highly stressed areas.
KeywordsPreventive Maintenance Longitudinal Force Harmonic Amplitude Railroad Industry Southwest Research Institute
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