Print Email Facebook Twitter Investigation of the formation of corrugation-induced rail squats based on extensive field monitoring Title Investigation of the formation of corrugation-induced rail squats based on extensive field monitoring Author Deng, X. (TU Delft Railway Engineering) Qian, Zhiwei (TU Delft Railway Engineering) Li, Z. (TU Delft Railway Engineering) Dollevoet, R.P.B.J. (TU Delft Railway Engineering) Date 2018-07-01 Abstract Rail squats originate from a number of sources, such as corrugations, indentations and welds. A five-year continual field monitoring study was performed on squats induced by corrugations. This study indicated that a small black depression formed at the corrugation under wheel-rail dynamic forces, and then, a primary crack typically initiated on the gauge side edge of the depression. Subsequently, the crack began to propagate in the rail surface in a U shape toward the gauge side in both the traffic direction and the opposite-traffic direction and into the rail toward the field side at an angle of approximately 20°. Rail inclination could influence the crack initiation location and propagation path. The geometry of the black squat depression was initially elliptical, and then, its edge followed the U-shaped cracking path as it grew. The squats turned into a kidney-like shape, typically with a U-shaped crack. Tensile stress likely led to the squat crack initiation and propagation. This cracking phenomenon and mechanism are analogous to the ring/cone crack formation of brittle materials under sphere-sliding contact. As the squats grew further, a ridge formed in the middle part of the depression, and an I-shaped crack appeared at this ridge due to the impact of the wheels. This process eventually led to two-lung-shaped mature squats, typically with a Y-shaped crack. The findings of this paper provide insight into the formation of rail squats. Subject Continual field monitoringCorrugationCrack initiationCrack propagationRail squatsRolling contact fatigue (RCF) To reference this document use: http://resolver.tudelft.nl/uuid:3ff16dcf-5892-4a59-847c-6e2decfdf902 DOI https://doi.org/10.1016/j.ijfatigue.2018.03.002 Embargo date 2018-09-08 ISSN 0142-1123 Source International Journal of Fatigue, 112, 94-105 Bibliographical note Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Part of collection Institutional Repository Document type journal article Rights © 2018 X. Deng, Zhiwei Qian, Z. Li, R.P.B.J. Dollevoet Files PDF 1_s2.0_S0142112318300860_main.pdf 2.16 MB Close viewer /islandora/object/uuid:3ff16dcf-5892-4a59-847c-6e2decfdf902/datastream/OBJ/view