The Construction of Rainbow Bridge 1: Introduction

Overall view of the Rainbow Bridge.

Structural form: Suspension bridge
Bridge length: 798m
Center span: 570m
Main tower height: (above sea level) 126m
Bridge’s inauguration: August 26, 1993

This series of articles will cover the construction of the Rainbow Bridge from 1987 to 1993. The Rainbow Bridge is the main transportation infrastructure that connects the Tokyo city centre to the waterfront sub-centre, also known as Odaiba. This infrastructure is the foundation for the future success of the 7th sub-centre of Tokyo in the making of the new image of the city in the 21st century[1]. This bridge is a multi-purpose transportation complex consisting of Route 11 Daiba Line, Harbor Road, and the Waterfront New Transit System (Yurikamome).

Light-up style of the Rainbow Bridge.
Light facility

In order to decide what kind of landscape the bridge should be to become the image of the new Tokyo, debates were brought up. The concern was not just about the main tower shape but also the colour and light-up style of the bridge, which was detailed in many proposals. The approved proposal demonstrated the harmony between the bridge and the future of the Tokyo Bay. Comments are made today that after 20 years since its construction, the design of the Rainbow Bridge does not show any signs of age and continues to delight many people as the symbol of Tokyo Bay. 

The bridge aimed to provide direct access between central Tokyo and the waterfront sub-centre by connecting two expressways on both sides of the port. By doing so, an express route across the city will be created to significantly ease the congestion issue in the centre of Tokyo. The bridge was designed to be a 3-span, 2-hinge stiffening truss suspension type with a centre span of 570 m and a total length of 798 m[2]. It has a double-deck construction: the upper deck carries two two-lane expressways, while the lower carries two two-lane roads serving the Port, as well as a railway and footpaths[2]. The diameter of the main cable is 762 mm. The bridge is founded on mudstone (consolidated silt or soft rock) far below the surface[2].

Reference:

[1]Yamazaki, K., Izumi, K. and Ogihara, M. “The Rainbow Bridge, Japan.” Structural Engineering International, v. 4, n. 4 (1994), 226-228.

[2]Metropolitan Expressway Company Limited. “Rainbow Bridge.” Driving Guide, (1995), 10-15.

[3]Tokyo Bureau Of Port and Harbour. Rainbow Bridge, (2015), 1-3.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.