Enhancing Railway Safety through Remote Monitoring of Railway Expansion Switches Using Linear Sensors in Continuous Welded Rail

This study examines how two types of simple linear sensors- a pull wire and a short-range acoustic sensor can monitor the movement of expansion switches in continuous welded rail. A full-scale lab setup was used to test how well these sensors measure rail overlap and gap under different temperature settings. Their readings were compared against benchmark values and thermal displacement estimates from both a basic expansion formula and Ansys finite element models. Results show that both sensors worked well within a practical temperature range, with small errors. At higher temperatures, the pull wire sensor showed slightly more deviation. The findings support the idea that these low-cost sensors could play a key role in ongoing rail safety monitoring, though further field tests are needed.