The Construction of Rainbow Bridge 2: Foundation
The construction of the bridge started in January 1987 which is 2 years after the first master plan of waterfront sub-centre. The official name of the bridge is the “Tokyo Harbor Connecting Bridge” while the name “Rainbow Bridge” was decided by the public. This bridge is part of the Route 11 Daiba Line expressway which links Route 1 Haneda Line and the Bayshore Route together. At the time, the route was meant to relieve traffic congestion towards the city centre by connecting the city centre and the yet-to-be-built Tokyo Waterfront Sub-center. That was not the only function of the Route 11 Daiba Line. It was also meant to provide a place of leisure with new scenery well suited for the new Tokyo Waterfront Sub-center. Finally, construction was started for a bridge that would combine both transit convenience and beautiful scenery.
The construction process lasted from 1987 to 1993. Its location near the Port of Tokyo which is pivotal to air, sea, and land transport put various constraints on design and construction methods, especially on the height of the main tower and shape of the bridge. Being next to Haneda Airport put constraints on the height of the main tower. In addition, the water route had to be wide enough for large ships to pass through the intricate bay interior. After various studies, the form of a suspension bridge was accepted. Constructing the Rainbow Bridge required overcoming these sorts of difficulties and constraints.
The main tower foundation was set up using the Pneumatic caisson method.
The anchorage is a giant block for anchoring the main cable, or suspension bridge’s wing.
Yamazaki, K., Izumi, K. and Ogihara, M. “The Rainbow Bridge, Japan.” Structural Engineering International, v. 4, n. 4 (1994), 226-228.
Metropolitan Expressway Company Limited. “Rainbow Bridge.” Driving Guide, (1995), 10-15.
Tokyo Bureau Of Port and Harbour. Rainbow Bridge, (2015), 1-3.