Track Geometry Degradation Modelling Considering Multiple Indicators

Railway infrastructure requires effective maintenance to ensure safe and comfortable transportation. Among the various degradation modes, track geometry deformation caused by repeated loading is a critical mechanism impacting operational safety. Detecting and maintaining acceptable track geometry relies on track recording vehicles (TRVs) that inspect and record geometric parameters. This study aims to develop a novel track geometry degradation model considering multiple indicators and their correlation, while accounting for both imperfect manual and mechanized tamping. A multi-variate Wiener model is formulated to capture the characteristics of track geometry degradation. To overcome data limitations, a hierarchical Bayesian approach with Markov Chain Monte Carlo (MCMC) simulation is utilized. This study offers a contribution on the analysis of a multi-variate predictive model which considers correlation between the degradation rates of multiple indicators, providing insights for rail operators and new track-monitoring systems. The performance of the models is rigorously validated through a real-world case study on a commuter track in Queensland, Australia, utilizing actual data and independent test datasets. This experimental calibration and validation procedure represents a novel contribution to the existing literature, offering valuable guidance for rail asset management and decision-making.