Forth Road Bridge Main Expansion Joints: Southbound Carriageway Works Complete

The Forth Road Bridge will be free of long-term roadworks for the remainder of this winter, with work to replace the main expansion joints in the southbound carriageway now complete.

Restrictions were lifted this morning and the full capacity of the bridge is now open to buses, taxis, and other vehicles permitted to use the public transport corridor.

The completion of these works means that the Forth Road Bridge can be used as an emergency diversion route, should the Queensferry Crossing have to close for an extended period.

Work to replace the main expansion joints in the northbound carriageway will commence in April 2021 and is expected to be completed by the end of October 2021.

Work to replace smaller joints in the west footpath will be carried out between January and April 2021. Some short-term lane closures will be required to allow components to be lifted in and out of position, but these will be rescheduled if the bridge is required for use as a diversion route.

Chris Tracey, BEAR Scotland’s South East Unit Bridges Manager, said:

“This is a significant milestone in what has been a challenging project. It’s good to see both carriageways on the Forth Road Bridge open again.

“The main expansion joints allow the bridge to expand and contract in response to wind, temperature and traffic loading. They performed well since the bridge opened in 1964 but had reached the end of their service life after over 50 years of heavy use.

“These joints were originally due for replacement in 2009, however the decision to build the Queensferry Crossing meant that the project could be postponed. This avoided massive disruption to traffic over an extended period, and significantly reduced the cost of the works by avoiding the need for expensive temporary bridges over the joints.

“The project has not been without its challenges. The pandemic resulted in a three-month suspension of work on site earlier this year and a subsequent modification of working practices. We also discovered hidden issues once we took the joints apart, including details that differed from the original construction drawings, and these required additional works to resolve.

“The Forth Road Bridge has continued to fulfil its function as a public transport corridor throughout this project, however the bridge will now be available to provide additional resilience as an emergency diversion route for motorway traffic, should the Queensferry Crossing have to close for an extended period this winter.

“It should be noted that an emergency diversion would only be implemented overnight, outside peak periods. This is because it takes several hours to remove roadside barriers and lay large numbers of cones and signs, and this process would cause significant additional disruption to traffic during busy periods.

“A trial diversion over the Forth Road Bridge will be carried out in January, with the aim of further refining this process.”

The replacement of the main expansion joints forms part of a significant investment by Transport Scotland to strengthen and refurbish the Forth Road Bridge following decades of heavy use. Other recent improvements have included the redesign and replacement of the truss end links, resurfacing of the approach viaducts and upgrading of underdeck maintenance walkways.