Reliability Analysis of Railroad Tracks

Abstract

The loads acting on railroad tracks due to the. passage of trains have a random character. Similarly, the track resistance parameters exhibit various degrees of randomness. The purpose of this study is to incorporate the random nature of the parameters in the analysis of railroad tracks. The changes in the reliability index are determined for variations of loads and track properties. A rail element is used in the analysis that can incorporate the lateral, torsional, and axial deformations, as well as warping of the rail section. In this analysis, the track components such as fasteners, ties, ballast, and subgrade are incorporated by a set of vertical, lateral, and torsional springs. The finite element method is formulated for the track system in terms of the random variables. The formulation is based on a linear statistical model using the first‐order‐second‐moment method. The reliability index is computed, using the Rackwitz‐Fiessler algorithm, for the limit state function found by the finite element solution. Using the computer program developed, a parametric study is conducted to investigate the effect of the various parameters on the reliability index.