Methodology for evaluating thermal track buckling in dual gauge tracks with continuous welded rail

Abstract

In the National Spanish railway network, two types of track gauge with continuous welded rails are currently in use: the “Iberian” wide gauge (1668 mm) and the standard gauge (1435 mm). In order to improve links and freight traffic between different lines and with the rest of Europe, a dual gauge track with three rails was developed. This solution modifies the classical track configuration, so it is necessary to develop new methodologies and studies to understand its behavior. Among other loads applied on a continuous welded rail track, a considerable rise in temperature induces compressive stresses in the three rails that can lead to lateral track buckling. Moreover, on dual gauge tracks, the addition of the third rail increases the axial compression, which may lead to track instability. For this reason, a three-dimensional continuous welded rail model is developed in this study to be used for dual gauge track buckling analysis on straight tracks subjected to temperature load. The continuous welded rail dual gauge track model consists of beam, solid and spring elements, in which a non-linear behaviour of the ballast is considered. The results obtained may be used to predict the buckling capacity of the continuous welded rail on dual gauge tracks with respect to different parameters such as lateral resistance, lateral imperfections, sleeper spacing or torsional stiffness.