Condition monitoring of crossing running surface geometry – a comparison between manual inspections and sleeper mounted accelerometers

Övrigt konferensbidrag, 2025

This study investigates eight crossings on the Western Main Line in Sweden to evaluate traditional manual geometry assessments using templates, and to compare them with condition indicators derived from sleeper-mounted accelerometers. High-resolution 3D scans of the crossing rails were used to virtually replicate the template inspection procedure defined by the Swedish Transport Administration. These scans also served as input for simulations of wheel–rail kinematics and dynamic vehicle–track interaction, enabling extraction of condition indicators for comparison, including sleeper acceleration and velocity metrics, as well as a wheel–rail kinematic parameter referred to as the dip angle. All indicators were evaluated based on their correlation with the maximum vertical wheel–rail contact force at the transition between the crossing nose and wing rail. The results show that template-based wear measures lack predictive capacity for generated impact forces, which raises the question of the use of these as condition indicators in a predictive maintenance context. Sleeper responses show stronger potential, and the dip angle shows high correlation as expected. This work provides insight into the critical role of crossing geometry, highlights limitations of current maintenance practices, and forms a basis for the development of continuous monitoring strategies for improved maintenance planning that better manage long-term mechanical deterioration.