Central Circular Route Yamate Tunnel Facility Design
|Project Duration||1985 to 2013|
|Completion of construction||All routes opened on March 7, 2015|
|Ordered by||Metropolitan Expressway Co., Ltd.|
Central Circular Route Yamate Tunnel has a tunnel length of approximately 18 kilometers, making it the longest road tunnel in Japan. Pacific Consultants was involved in the planning and design of a wide range of attached tunnel facilities including ventilation, lighting and disaster risk reduction and management equipment, and significantly contributed to the tunnel project. With the continual introduction of the latest technologies such as LED lighting and wind speed control in the event of fire along with a design that pursued cost savings and convenience, we have contributed to a project benefiting society.
The Yamate Tunnel is the longest in Japan and boast the second longest tunnel length in the world, behind the Lærdal Tunnel in Norway. It also features a complex structure with in-tunnel branching due to the entrances and exits unique to a city tunnel, and connections with ventilator stations. Even under these conditions, innovative solutions were employed, such as the securing of equipment space under the road to ensure equipment functioning, and the use of mist to lower road temperatures.