Investigation Into the Calculation of Superelevation Defects on Conventional Rail Lines

Abstract

Railway curves have influence on train speed on a curve and/or wheel/rail interface. Additional forces that have to be compensated appear in the curves. The purpose of superelevation is to compensate acceleration emerging in the curve thus assuring comfortable passenger transportation and equal wearing of both rails. However, it is very difficult to calculate superelevation when designing and maintaining a railway track, because the estimation of actual train speed on the curves is very complicated. As we know, railway lines can be divided into conventional, high speed and heavy haul ones. As these lines are absolutely different, requirements for the installation and maintenance of the track may also differ. Conventional rail lines are the object of research discussed in this article. The speed of freight and passenger trains is different on conventional rail lines, which is an essential factor in determining superelevation. On the ground of scientific researches, the article analyzes and evaluates the factors influencing wheel/rail interface on the curves. The paper also deals with railway line curves, superelevation and uncompensated lateral acceleration. The article presents the method used in Lithuania for calculating superelevation in the railway curves and analyzes calculation defects. For research purposes, analytical and statistical methods have been used. The obtained results have shown that actual superelevation in the researched curves does not match the calculated one. The calculations and obtained results of superelevation depend on how average train speed in the curves is estimated and used for calculations. As most of the results show that even small variations in the curve have a great influence on track/vehicle behaviour, it is necessary to find more precise methods for calculating superelevation, evaluating actual train speed and considering permissible uncompensated lateral acceleration in the curves.

Approach to Rational Calculation of Superelevation in Dual Gauge Track

“…Therefore critical speed should be included into operational requirements together with the greatest permissible train speeds. This speed is calculated by using (Gailienė 2012…”

“…When the wheels slide on internal rail the wear of external rail is smaller, however the train can derail. When the wheels slide on internal rail the wheel flange wear increases (Gailienė 2012).…”

“…In this paper, we analyse the applied methodology for calculation of the superelevation and seek to identify its shortcomings. We also employ our earlier published research results (Gailienė 2012;Povilaitienė, Laurinavičius 2004;Povilaitienė 2004) to make recommendations for improvement of the methodology for calculation of the superelevation. This way we seek to make the railway traffic safer and more comfortable and to ensure the least possible wear of the rail.…”

Railways in Lithuania: From Tsarist Russia to Rail Baltica

“…Lithuanian scientists are researching railway transport infrastructure, rolling stock and transportation processes. The research by Gailienė (2012) presents the method in Lithuania for calculating superelevation in the railway curves and analyses calculation defects. Navikas et al (2018) presents investigation and evaluation of railway ballast properties variation during technological processes.…”

Theoretical and experimental study on vertical dynamic characteristics of six-axle heavy-haul locomotive on curve

“…Based on the comparisons of the vehicle system dynamic responses for different transition curves, Long et al (2010) and Zhang et al (2010) gave some suggestions to the railway curve design. For the conventional railway lines, Gailienė (2012) analysed the calculation defects of curve superelevation. It is explained clearly that more precise methods for calculating superelevation, evaluating actual train speed and considering permissible uncompensated lateral acceleration in the curves should be found.…”