Estimation of sleeper-ballast contact pressure based on fretting marks: field measurements and FEM modeling

The contact conditions between components of railway infrastructure are complex. This research focuses on the contact interactions between the ballast and steel sleepers. Unlike the prismatic design of concrete and wooden sleepers, steel sleepers are characterized by a unique U-shaped configuration, further contributing to the complexity of the contact conditions. To address this issue, this study focused on analyzing the lower surfaces of steel sleepers commonly used in railroads, which had contact marks resulting from the ballast and train load due to fretting. To simulate these contact marks, virtual ballast geometries were created and simplified to match the observed contact areas. Specifically, these contact areas represented 6% of the bottom area of the steel sleepers. We compared the efficiency of this approach using Finite Element Method simulations.