Harsh Conditions in Hsuehshan Tunnel Leads to Selection of NPort 5230 Device Servers

Release Date : 2006-10-10

Shing-Tien, Taiwan, October 11th, 2006—Taiwan's Hsuehshan Tunnel, known for its difficult construction as well as for being one of the world's longest road tunnels, has installed NPort 5230 device servers for its traffic control system. The NPort 5230 device server was selected for its rugged, industrial-grade construction and is used to manage each of the tunnel's ten traffic control gates remotely over the network.

The successful construction of Hsuehshan Tunnel is widely considered a feat of engineering and human perseverance, due to the number and severity of engineering challenges that were faced. At 12.9 km, it is the longest road tunnel in East Asia and the fifth-longest tunnel in the world. The tunnel cuts through Snow Mountain, known as Hsuehshan by locals, which is the second highest mountain in Taiwan at 3886 meters. Construction was almost abandoned several times because of problems caused by the site's complex geology, including many fracture zones, high-pressure groundwater, and major fault lines. During the 15 years that were spent on Hsuehshan Tunnel's construction, the ground reportedly collapsed 98 times, underground water inundated the tunnel 36 times, tunnel boring machines were trapped inside 26 times, and 25 workers lost their lives. The tunnel's great length and difficult environment made it critical that a comprehensive, reliable, and safe management system was established.

Hsuehshan Tunnel selected Moxa's NPort 5230 for use in its traffic control system, based on Moxa's experience with automated traffic monitoring systems as well as its excellent reputation for reliability and ruggedness. Ten traffic control gates along the length of Hsuehshan Tunnel required management over a network from a central location. During emergencies such as fire, flood, or earthquake, the control center needed the ability to selectively lower different gates in order to control or halt traffic flow into the tunnel. Moxa's NPort 5230, which makes serial devices accessible over Ethernet , provided each gate with a connection to the network, enabling remote access from the control center. Another Moxa product, the EDS-508, was used to manage network connections to and from the control center. Both the NPort 5230 and the EDS-508 were designed for ultra-reliable operation in harsh, industrial environments, making them a natural fit for the often extreme conditions encountered in the tunnel.

Traffic Control Gate Hsuehshan Tunnel was opened to the public in June of 2006. It consists of two primary tunnels, a pilot tunnel for service and maintenance, a network of interconnecting pedestrian and vehicle tubes, and almost 2000 kilometers of wiring and fiber optics for lighting, firefighting, communication, computer-monitoring and traffic control systems. Automated road-rule enforcement cameras run the length of the tunnel to monitor speeders, tailgaters, and illegal lane-changers. It takes about twenty minutes to drive from one end of the tunnel to another, and the total drive between Taipei City and Yilan County has been reduced from over two hours to less than forty minutes.