Simulating the effects of structural discontinuities on the long-term behavior of the ballasted railway track

Abstract

Structural discontinuities in railway tracks have proven challenging from a maintenance perspective. These discontinuities can lead to uneven settlements, reducing serviceability of the railway network and increasing the track’s dynamic loading. To optimize the long-term performance of railway structures, it is essential to evaluate different design solutions under varying loading conditions to identify potential risk factors early. Consequently, this study proposes a novel computational model for simulating the dynamic long-term behavior of ballasted railway tracks. The proposed model enables computationally efficient simulation and provides an innovative mathematical framework for analyzing the mechanical behavior of structural discontinuities, allowing detailed consideration of substructure and subsoil properties, including their variations along the longitudinal direction of the track. Simulations were conducted to investigate the effects of bridge transition zones and rail defects on the short- and long-term behavior of the track for two vehicle types. In addition, extensive field measurement data were utilized for model verification. Based on simulations, the axle load appears to be the primary factor influencing the long-term performance of railway transition zones. However, for more localized defect types, the significance of driving speed and the unsprung mass of rolling stock becomes more pronounced. Overall, the findings highlight the nonlinear relationship between vehicle loading and structural deterioration, emphasizing its strong dependence on track properties.