Rockfall detection

Up to 80km of railway monitored 24/7

Distributed Acoustic Sensing (DAS), allows a single fiber optic sensing unit to monitor up to 100km of standard telecoms fiber from a single secure location. That equates to around 80km or 50 miles of railway route that can be monitored for rockfalls by each sensing unit. No longer do you have to accurately predict where a rock fall may occur as entire routes can be monitored in real time.

This long-range monitoring capability also makes detecting rockfalls much more simple and cost effective in remote areas where power and communications access may be severely limited. By siting railway monitoring technology in existing signalling or equipment rooms, operators can achieve massive network visibility without the logistical burden of installing and powering thousands of individual point sensors across large geographic distances.

Weather and interference resilience built-in

Buried or below ground fiber optic cables are inherently protected from the destructive forces of nature. While trackside poles, antennas and sensors can be damaged by storms, an underground fiber cable remains operational so long as it is not physically broken.

Fiber optics are also immune to Electro-Magnetic Interference (EMC) from both railway sources such as traction power systems, signalling systems or external interferance both accidental or intentional. This immunity to remote tampering and interferance minimises the potential for false alarms or compromised detection sensitivity ensuring the railway continues to be monitored for rockfalls whatever the weather.

Gap-free railway rockfall detection

Traditional rockfall detection relies on networks of point sensors set up to monitor high-risk locations, or reactive reports from train drivers/engineers. Point sensors such as wire-break, tilt, or displacement sensors can be used to monitor a single specific spot where they are installed, but this risks accidents happening due to rockfalls between sensors. Increase the sensor density to close gaps makes costs spiral and full route coverage is impractical and uneconomic. 

Fiber optic sensing turns the entire length of a buried cable into a gap-free high-fidelity sensor array, providing 100% spatial coverage along its length no infrastructure "blind spots." This gapless detection ensures that regardless of where a rockfall occurs, even in unexpected areas, the system can identify the ground impacts from the falling rock, providing superior reliable route-wide protection.

No on-site maintenance

Traditional approaches to rockfall detection often rely on battery powered sensors that often require physical on-site reset after a real or indeed false alert. CCTV or LiDAR based rockfall sensing requires regular cleaning to keep them effective as well as often mains power supply. 

Fiber optic sensing requires neither trackside power or batteries, nor regular on-site maintenance. Because the sensing element is a passive glass fiber, there are no components to wear or require calibration or replacement in the field. This results in a truly scalable, low maintenance solution that reducing or eliminating site maintenance, visits lowering long-term operational costs.

No Reliance on Radio Communications

IoT-based sensor solutions depend on cellular, radio or wi-fi networks to transmit data and alerts. Those same radio networks are stressed during extreme weather events, the same weather events that exacerbate rockfall risk. Radio communications are also vulnerable to external interferance sources both natural and nefarious. 

Fiber optic sensing uses the fiber itself as both sensor and data carrier, meaning data is transmitted via light by the fiber to safe and secure equipment and signalling rooms for monitoring. This immunity to accidental or intentional interference, signal disruption, or network congestion ensures that critical rockfall alerts reach the operations centre reliably in real-time, despite any external influences such as weather.