JFE Engineering Wins Contract for Seismic Retrofit Project on Kurushima Kaikyo Bridge
—Large-Scale Seismic Retrofit Project to Protect the Vital Artery of the Shimanami Kaido Expressway from Earthquakes—
JFE Engineering Corporation
JFE Engineering Corporation (Representative Director: Kazuyoshi Fukuda; Head Office: Chiyoda-ku, Tokyo) has received an order for the Kurushima Kaikyo Bridge Seismic Retrofit and Related Construction ("Project"), commissioned by Honshu-Shikoku Bridge Expressway Company Limited ("HSBE").
The Project involves seismic retrofitting of the First, Second, and Third Kurushima Kaikyo Bridges (total length: approx. 4 km), located on the Ehime Prefecture side of the E76 Nishi-seto Expressway (Setouchi Shimanami Kaido), to prepare for major earthquakes.
The Kurushima Kaikyo Bridge is the world’s first bridge complex consisting of three consecutive suspension bridges, crossing the approximately 4-km-wide Kurushima Strait between Oshima Island and Imabari City, Ehime Prefecture. Since its opening in 1999, it has served not only as a vital transportation link connecting Honshu and Shikoku but also as essential infrastructure supporting local residents' daily lives and tourism activities such as cycling. In addition to the expressway, the bridge features dedicated lanes for motorized bicycles and pedestrians, serving a high volume of vehicles, foot traffic, and cyclists. JFE Engineering, which participated as a member of the joint venture that constructed the Third Kurushima Kaikyo Bridge (total length: 1,570 m), will leverage the expertise and technologies it has cultivated in building long-span bridges to undertake this Project.
The principal scope of the Project is as follows:
- Existing center stays *1 and side stays*2 will be replaced with high-damping friction dampers*3, significantly improving bridge safety by absorbing and dissipating seismic energy through friction.
- Newly installed vibration-control dampers*4 will control seismic vibrations, effectively reducing the risk of damage to bridge piers and of bridge collapse.
- Reinforcement structures and other measures will be applied at the bearings*5 to prevent girder collapse and secure the girders in the longitudinal direction during earthquakes, while also mitigating impact when girders collide during seismic events.
The Project aims to enhance the seismic performance of the Kurushima Kaikyo Bridge. Even in the event of a major earthquake exceeding assumed scenarios such as a Nankai Trough megaquake, the Project is expected to support the rapid restoration of service and help maintain the route’s function as an emergency transportation corridor and facilitating the development of resilient road infrastructure.
JFE Engineering has long been involved in the construction and maintenance of bridges managed by HSBE. For this seismic retrofit project as well, we will bring together our comprehensive expertise in the design, fabrication, and erection of steel bridges to ensure the successful completion of work that safeguards the safety and reliability of the Shimanami Kaido.
- *1 A device located at the center of the bridge that connects the main cables to the bridge girder (stiffening girder).
- *2A structural member installed at the ends of the bridge (girder ends) to mitigate the effects of temperature changes, earthquakes, and wind.
- *3A seismic damping and vibration-control device that converts vibration energy generated by earthquakes and strong winds into thermal energy through friction, efficiently absorbing bridge vibrations.
- *4A device that absorbs and dissipates vibration energy caused by earthquakes and wind to prevent damage to bridge girders and piers.
- *5A component installed between the superstructure (bridge girder) and substructure (bridge piers and abutments) that accommodates expansion and contraction caused by temperature changes and loads.
Construction Overview
| Project name | Kurushima Kaikyo Bridge Seismic Retrofit and Related Construction |
|---|---|
| Client | Honshu-Shikoku Bridge Expressway Company Limited |
| Project location | Kamiura-cho to Sunaba-cho, Imabari City, Ehime Prefecture (KP29.605 to KP54.140) |
| Contract amount | ¥4,356 million (including tax) |
| Construction period | August 1, 2026 – October 13, 2029 (1,170 days) |
About the Kurushima Kaikyo Bridge
The Kurushima Kaikyo Bridge is one of the bridges comprising the Nishi-seto Expressway (Setouchi Shimanami Kaido), which opened in 1999. Located in Imabari City, Ehime Prefecture, it is the world's first triple-suspension bridge complex, crossing the approximately 4-km-wide Kurushima Strait between Oshima Island and Imabari City. Consisting of three consecutive suspension bridges the First Bridge (960 m), the Second Bridge (1,515 m), and the Third Bridge (1,570 m)—the complex includes the expressway as well as dedicated lanes for motorized bicycles and pedestrians. It is a premier destination for cyclists, attracting visitors from Japan and abroad.
Source: Kurushima Kaikyo Bridge | Shimanami Kaido新規ウィンドウを開きます
For inquiries regarding this press release, please contact:
- Public Relations Section, General Administration Department, JFE Engineering Corporation