Danish consultant, Cowi, in JV with Daewoo Engineering Co (DEC), recently won the contract to design the Busan-Geoje Link in Korea, which includes a 4km long immersed tunnel, believed to be one of the longest in the world.
The project involves an 8.2km long motorway connecting Busan, Korea’s second largest city, to the island of Geoje. There will also be two 2km long cable-stayed bridges.
“Although smaller than both the Øresund link and Denmark’s Great Belt bridge, the extensive experience Cowi gained on these projects has helped win us the Korea contract,” Cowi divisional director, Anton Petersen, said. “This project stands Cowi in further good stead for future fixed links.”
The main immersed tunnel will be 3,384m long, 8m high and 29m wide, with cut and cover troughs at the east and west portals. The construction of the tunnel presents several challenges, the main one being the depth – it will lie 50m below the surface at its deepest point. This could cause difficulties with the watertightness of joints, the preparation of tunnel supports and the placing of individual elements. The soil conditions, which are very soft marine clay for the majority of the alignment, could also cause problems.
The owner of the link is Busan Metropolitan City and Gyeongnam Province, who awarded the BOT contract to construct the link to GK Fixed Link Corporation. COWI/DEC JV is designing the link, while Daewoo Engineering and Construction Co (independent from DEC) is the main contractor for link.
Construction is expected to start in 2004, with a scheduled completion date of 2009.
