Numerical investigation of the effect of variable subsoil conditions and freight traffic on railway infrastructure

For the freight railway it is fundamental to gain competitiveness with respect to the other transportation modes. This can be obtained by new freight vehicles running at higher speed and higher tonnage under controlled conditions over a more resilient infrastructure. The new traffic conditions impose higher dynamic loads on the infrastructure which need to be carefully analyzed. In particular, for the track itself to maintain its geometry for the longest time (under various traffic conditions), it is important that the substrate would remain stable as far as is reasonably practicable under the influence of other external factors such as climatic effects (temperature, groundwater content, etc). This study focuses on the role of track substrate and structure in enabling the railway to effectively bear the higher dynamic loads from new generation of freight vehicles. The impacts of substrate stiffness variation on track geometry deterioration and other track defects is investigated with attention paid to specific freight train typology (namely flat bed wagon), to different loading conditions (from full laden to tare) and speeds at “critical” track locations (e.g. transitions onto and off bridge, abutments, etc.).