Estimating the total risk for a sun-kink by measuring wave propagation in the track
2016 (English)In: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit, ISSN 0954-4097, E-ISSN 2041-3017, Vol. 230, no 3, p. 734-746Article in journal (Refereed) Published
Abstract [en]
A method to estimate the stress-free temperature in a rail by exciting the complete track has been theoretically investigated, by both simple beam theory and by a finite element model. For frequencies below a cut-off frequency, bending waves cannot propagate in the track. The cut-off frequency primarily depends on the stiffness of the lateral ballast. For a given ballast stiffness, the wavelength (or speed) of propagating waves depends on the axial stress in the rail. By first determining the cut-off frequency, the ballast stiffness can be determined. Then, the actual stress can be estimated by measuring the wave speed. By knowing the actual rail temperature, the stress-free temperature is then easily calculated. It is found that stress-free temperatures of 5 °Cshould cause measurable changes in the speed of wave propagation. It is determined that variations in damping of the ballast and stiffness of the pads in the rail clamps do not influence the results. Field measurements show that a track can be excited and propagating waves detected.
Place, publisher, year, edition, pages
2016. Vol. 230, no 3, p. 734-746
Keywords [en]
dispersion, guided wave, propagating waves, rail, Railway track, stress-free temperature, track buckling, track stiffness, Dispersion (waves), Finite element method, Guided electromagnetic wave propagation, Rails, Stiffness, Wave propagation, Wave transmission, Risk perception
National Category
Applied Mechanics
Identifiers
URN: urn:nbn:se:ri:diva-27656DOI: 10.1177/0954409714562491Scopus ID: 2-s2.0-84975718153OAI: oai:DiVA.org:ri-27656DiVA, id: diva2:1059482
2016-12-222016-12-212020-12-01Bibliographically approved