More refurbishment work than at first thought is needed after grit blasting finished on the Corporation Road Bridge in Grimsby, northern England.
Grit blasting to the undersides of the bascule bridge, nearly 100 years old, for spans one through four allowed a detailed inspection of the structure. The timber lifting deck was removed and a temporary deck installed while work continues, according to the Spencer Group, the principal contractor on the project and which has carried out maintenance and repair work on some of the UK’s most iconic bridges, including the Humber, Forth, Erskine, Severn and Menai bridges.
Harsh environmental conditions, including the salt water of the Alexandra Dock water over which the bridge crosses, has led to higher degradation of the steel structure than expected. This has required further designs to be added to the scope of works in addition to further physical repairs.
Steel repair work has begun both above and below deck, with painting work progressing as repairs permit.
Encapsulation and scaffolding are now fully erected to the north side of spans five and six above deck, preventing dust, debris and adverse weather from affecting the work in progress. Grit blasting is progressing on these sections as well.
Detailed design work to the bridge lifting control room has now been completed with work due to start in the next few weeks, according to the client, North East Lincolnshire Council.
Restoration work including structural renovation and aesthetic improvements started in February last year on the heritage listed bridge and will cost around €5 million. Spencer Group said the bridge will remain open to pedestrians and cyclists, except during short periods when the contractor will need to test the lifting mechanisms and the bridge will need to be fully closed.
Equans, part of the Bouygues Group, is project manager for the work which are expected to take 11 months to complete.
Corporation Road Bridge is a relatively rare Scherzer rolling lift bascule bridge, as noted by Equans. The rolling lift trunnion - sometimes a Scherzer rolling lift bridge raises the span by rolling on a track resembling a rocking-chair base. The Scherzer rolling lift is a refinement patented in 1893 by American engineer William Donald Scherzer.
The Grimsby bridge was built in 1928 to replace an existing swing span bridge to allow shipping traffic access to the former fishing dock from inland waters. Although little shipping uses the river, undertaking the works will allow the bridge to be removed from the “heritage-at-risk” register.
“The bridge is a key structure the borough and these works will help to protect this landmark for many years to come and preserve its Grade II listed heritage status,” said Neil Foster, Equans’ project manager on the North East Lincolnshire contract.
To keep up to date with the Corporation Road Bridge works, click here.
