Bypass Tunnel, Lungern, Switzerland
Advanced safety technology for bypass tunnel
The 3.57 kilometers long Lungern Bypass Tunnel opened in December 2012 in the Canton of Obwalden. It was a decade-long construction project that stands out from other Swiss tunnels for two reasons: the end-to-end LED lighting, and, more importantly, the high requirements for safety, measuring, and monitoring equipment.
To ensure optimal tunnel safety, the Canton of Obwalden put great emphasis on infrastructure measures, especially high-quality security, fire safety, measuring and surveillance equipment. As with the previous bypass tunnel of the A8, it relied on proven expertise and the experienced team from Siemens.
Siemens supplied the video surveillance as well as the fire and smoke detection systems. The best FibroLaser technology was used here, which is based on linear, thermal fire detection using fiber-optics. In addition, smoke sensors were mounted directly on the ventilation dampers at intervals of approx. every 100 meters. In case of fire, the smoke gases at the location of the fire are drawn through the ventilation dampers.
The most important auxiliary equipment for autonomous operation is complete video surveillance of the tunnel and portal areas. Forty-four cameras in the tunnel and four in the outdoor area provide data to the video surveillance software Siveillance Tunnel.
The FibroLaser technology ensures rapid detection and precise-to-the-meter localization of the fire source. The combination with smoke sensors in the ventilation flaps exploits synergies and reduces the need for cabling. Thanks to sophisticated algorithms, the video surveillance automatically detects events such as stopped vehicles or traffic jams and forwards information via the A8 plant control system to the police station in Sarnen. In this way it is possible to respond quickly and appropriately in the event of an incident.
Video surveillance with