What was the issue?
Technologies such as Communication Based Train Control (CBTC) are emerging as efficient and cost effective for train position detection, replacing signalling systems based on track circuits.
A secondary function of the track circuit has been to detect broken rails, avoiding potential train derailments and so new technologies for detecting broken rails are urgently required in order to adopt these new train control systems.
What was done?
Literature review of potential detection systems, defining a broken rail as rail fully cracked through or when part of the running surface is lost.
Both track-based and vehicle-based broken rail detection systems were reviewed.
What was found?
No single existing technology that can accurately guarantee to detect 100% of broken rails or prevent 100% of broken rail occurrences.
Hybrid systems could be the most promising avenue for further research.