A computational procedure for prediction of ballasted track profile degradation under railway traffic loading

Abstract

A computational procedure is developed in the present paper, allowing the prediction of the ballasted track profile degradation under railway traffic loading. In this procedure, an integration of the short-term and long-term mechanical processes of track deterioration is taken into account, using a track degradation model. This degradation model is incorporated into a finite element code where two modes of calculation are implemented: the ''implicit mode'' concerns the short-term track deterioration, in which the hypoplastic model is used for the ballast layer and the dynamic response to an instantaneous train axle passage is obtained to serve as input data for the ''explicit mode'', which concerns the simulation of long-term track deterioration, using the accumulation model for ballast layer. The whole procedure is illustrated on the prediction of the ballasted track profile degradation of a track section of 100 m. The results show a significant influence of the type of track geometry defects and the vehicle velocity on the evolution of track deterioration and the capability of the proposed procedure in reproducing the track profile degradation.

Multiobjective Optimization for Railway Maintenance Plans

“…Mechanistic models are based on a simulation of the track geometry taking into account physical factors such as ballast and sleeper type, weather conditions, workload and wheel geometry. These models provide insight into the behavior of different components of the railway infrastructure from a physical point of view; however, their use for predictive modeling is hindered by large uncertainties (Nguyen et al 2016). Stochastic approaches produce a model from data measured from the tracks themselves.…”

A model for the stochastic prediction of track support stiffness

“…Nguyen et al 29 described an approach to track geometry prediction based on a finite element representation of the track with input geometry from real track. A track settlement relationship was implemented relating plastic strain to stress, and the analysis was run to predict settlement along a case study section of track.…”

Settlement analysis using a generic ballasted track simulation package

“…However, this model is developed on the basis of axisymmetric stress conditions. It is limited to two-dimensional problems and cannot be applied directly to dynamic problems [29]. A 2D full-track model using Hardening-Soil (HS) model combined with hypo-elastic material for ballast was introduced in Indraratna et al [30] and extended to three-dimensional (3D) by Kalliainen et al [31].…”

“…Commercial FE software, such as Abaqus and Ansys, are commonly used due to their efficient solver and mesh generation even for a complex geometry. Although the material constitutive model is limited and cannot correctly model the ballast behaviour ( [32,33]), a more detailed material constitutive law can be derived using user-subroutines in Fortran ( [29,34,35]). The implementation of new material constitutive law is not only complicated but also computationally time consuming due to data exchange between the FE software and Fortran ( [34,36,37]).…”