Fast Transportation from North to South: The New Kyushu Shinkansen High Speed Line in Japan

A few years ago, construction of a new line for the Shinkansen bullet train began on the island of Kyushu in Southern Japan. The line runs from south to north through the entire island, creating a much faster connection to Japan’s main island than previous railway connections.

Construction of the Kagoshima route started in 1991, and the first, 128km long section of the new line from Shinyatsushiro city to the district of Kagoshima was opened in 2004. According to plans, the Kagoshima route will extend for a total of 257km.

A new bridge was constructed for one of the sections. The Ohnogawa Bridge crosses the Ohno River near Uki City, in the centre of Kyushu Island. The new structure is a fourspan continuous cable-stayed prestressed concrete bridge. The extradosed bridge has a main span of 113m. The bridge project included the construction of supporting pneumatic caissons and four substructures for cast-in-place reinforced concrete piles.

DSI’s licensee in Japan, Sumitomo, supplied external Type 27S15.2 MC DYWIDAG Tendons with epoxy-coated strands as transverse post-tensioning tendons. These tendons were anchored inside the beams on the main girder side in order to minimize salt damage from the tidal Ohno River. Transverse Post-Tensioning of the deck slabs was carried out using prestressed individual strands.

The main tower saddle sections were prefabricated to ensure high product quality and on-site installation precision; this also helped reduce labor requirements at the construction site. The first trains will cross the new bridge in the spring of 2011.