Next case study
NSH Pontoon Package – HMNB Clyde
View case study
Forth Road Bridge
After a major structural fracture was discovered, Cairnhill was awarded a £3.6m contract to design, fabricate, and install new truss end links to enable the bridge’s safe reopening. The works replaced the damaged elements with a bespoke sliding bearing system, providing a durable long-term solution with minimal disruption.
OVERVIEW
Cairnhill was contracted by Spencer Group to design, fabricate, and install 7nr Truss End Link Replacement on the fully operational Forth Road Bridge, Edinburgh.
THE CLIENT
Spencer Group is one of the UK’s largest privately owned disciplinary businesses, providing a range of engineering services across transport, infrastructure, and energy sectors, supporting the development of civil and structural engineering.
Following the award of a £3.6m, 3-year contract in 2017, Cairnhill was tasked with the design, fabrication, and installation of new truss end links after a major fracture was discovered in 2015. The failure occurred on the Northeast main span in a link connecting the bridge deck to the tower, supporting areas without suspension cables. With its integrity, the bridge was forced to close until a safe and permanent solution could be delivered.
The response demanded both technical precision and the highest standards of quality. The long-term solution was to replace the fractured truss ends with a permanent sliding bearing system, capable of delivering reliable performance under the constant weight strain of the bridge. The work was complex, located in inaccessible areas beneath the bridge deck, and required precise planning and execution. Temporary brackets were installed on the main towers to support the structure during replacement, allowing the bridge to reopen safely with minimal road disruption.
Cairnhill fabricated new steelwork and bespoke sliding bearings to exact specifications, ensuring durability and accuracy. The tower cells were also strengthened to carry the combined weight of the new system, enhancing the structure’s resilience and performance. Throughout rigorous fabrication and installation processes, the project not only restored the bridge’s safety but also ensured that the replacement system would deliver dependable long-term performance.
