Longest bi-directional road tunnel planning for phased construction in Korea

The bi-directional road tunnel longest in Korea is to be constructed in Baehooryung area as part of Korea National Road 46. It is a single tube tunnel with a length of 5,057 meters in two lanes including service tunnel along its full length with cross passages at every 180 meter interval connecting both tunnels. One more tunnel will be supposed to be constructed at the location of the service tunnel for proposed road extension to four lanes (two one-way tunnels) in uncertain future. The tunnel plan focused on its safety from fire and the road extension work. Due to the tunnel length, traffic direction and uncertainty about extension, a fully-transverse ventilation system and a spacious roadway shoulder width are adopted for this tunnel. In this project, the service tunnel is multi-purposely used for the pilot tunnel during the main tunnel excavation, the emergency evacuation route in tunnel fire, and the enlargement excavation in future extension work. This paper introduces a very long road tunnel with very poor traffic condition and describes its safety measurements from tunnel fire and phased construction plan. (A) This paper was presented at Safety in the underground space - Proceedings of the ITA-AITES 2006 World Tunnel Congress and the 32nd ITA General Assembly, Seoul, Korea, 22-27 April 2006. For the covering abstract see ITRD E129148. “Reprinted with permission from Elsevier”.