Road traffic tunnels tend to be the most challenging parts of the roads when it comes to the administration of traffic and environmental conditions. In particular city centre tunnels are heavily populated with the traffic and tunnel control systems need to instantly react to traffic situation changes, possible hazardous situations and start preventive actions immediately.
Tampere road tunnel is the longest (2.4 km) and technically most advanced road tunnel in Finland. During years 2013 – 2016 Nodeon designed, implemented and commissioned management system and telecommunication network for the tunnel which was opened for traffic in November 2016.
Covering situational awareness
In Tampere, accurate traffic situation awareness is confirmed with almost 150 incident detection and CCTV cameras as well as inductive loops placed under the road surface. All incidents inside the tunnel are recognized by applications analyzing incident detection camera streams and with loops. The tunnel air quality, air flow and visibility are analyzed in more than 30 different observation points. The tunnel roof consists of 16 kilometres of fibre-optic heat detection cable, which recognizes possible fires with an accuracy of a couple of meters. All this makes sure the instant recognition of hazardous situations, as well as correctly targeted and adjusted safety procedures.
Traffic fluency and safety guaranteed with safety technology
Accurate situational awareness enables efficient tunnel management. The tunnel management system is the key element, confirming the interoperability between data collecting, traffic controlling as well as all other tunnel subsystems. Over one hundred changeable traffic controlling signs take care of the traffic safety and fluency inside the tunnel. Over 75 air blowers push air into the massive air conditioning pipes and keep the air fresh inside the tunnel. Lighting is automatically adjusted, so that lighting level at the entry and exit points correlates to the outside lighting. Tunnel also consist unique active fire protection method with fire sprinkler system.
Comprehensive safety technology also needs heavy infra systems. Electric power for the tunnel systems is distributed by a 20 kV high-voltage distribution system commonly used in electric distribution company networks and the water treatment capacity in the tunnel is comparable to a large spa. Coverage for VIRVE (network for Finnish authorities, such as the police, fire department) and mobile network is guaranteed inside the tunnel, from where you can also have a direct telephone connection to the rescue department at 50 different points.
All of this does not necessarily come to one’s mind while driving through the tunnel.