Construction of D-Runway at Tokyo International Airport

In August 2010, the fourth runway called D-Runway (2,500-m long) was completed off the shore of the Tokyo International Airport (Haneda Airport), which is the fourth largest airport in the world in terms of passengers handled. Since the D-Runway is situated at the mouth of the Tamagawa River, a hybrid structure combining a piled-elevated platform and land reclamation was planned so that it would not obstruct the flow of the river. In the reclamation area, a slope-type rubble mound seawall was constructed on the soft clay seabed, which was improved using the sand compaction pile method, with a total of 52 million cubic meters of soil, sand and rock used in the land reclamation. The piled-elevated platform is a massive 520,000-m2 structure in which 198 prefabricated steel jackets supported by 1,165 steel-pipe piles were connected together by welding on site. This project required huge quantities of construction materials, including 470,000 tons of steel and 450,000 m3 of concrete. The D-Runway was successfully constructed in just three and a half years thanks to the rapid construction method and a continuous 24-hours-a-day work schedule. This paper outlines the D-Runway project and its main structures.