Development of Expressway network
Promoting the development of Expressway networks while deploying various technologies to create day and night
Construction of tunnels in urban areas
Shield machines are used for tunnel construction in urban areas such as the outer ring road and Ken-O Road Expressway. In particular, the outer ring road (between the Kan-Etsu Expressway and the Tomei Expressway) uses a machine with a diameter of about 16 m as the largest cross section in Japan.
Girder construction of various bridges
When constructing a bridge, the crossing roads are closed at night and the girders are erected all at once by a multi-axle trolley. Since it is difficult to install a crane in mountainous areas or on rivers, the cable erection (direct suspension) construction method is used. The erection construction method according to local conditions is adopted.
Special earthwork site
At the site of the Tohoku Chuo Expressway, we pass through the wetland of Lake Hakuryu, so we took measures to soften the soil by the vacuum consolidation method in order to increase the strength of the soil. In addition, during the construction of Domanzan, which is a long-cherished earth slope, countermeasures were taken using rock bolts and concrete glue frames to prevent collapse.