New deck for A30 Dunheved Bridge, Launceston UK
United Kingdorm – Work starts later in april 2006 on a GBP3.8 million project to replace the bridge deck on Dunheved Bridge over the River Tamar on the Devon-Cornwall border.
The work involves replacing the existing bridge decks, with newly reinforced steel and concrete decks and will be completed in March 2007.
The innovative project involves building one of the new decks on temporary supports and then sliding it into place once the old deck is demolished, while maintaining the flow of traffic.
Highways Agency project sponsor, Lynton Cocks, said: â€œReplacing the bridge decks in this way allows us to keep the traffic flowing on the A30 while the works are in progress. We are anticipating only a low risk of delays during the project.â€œ
The embankment on the south side of the A30 will be widened at the bridge and the new westbound deck constructed on temporary supports. Two lanes of traffic will be maintained in each direction for the majority of this phase.
Westbound traffic will then be diverted onto the new westbound deck and eastbound traffic onto the existing westbound carriageway. The existing eastbound deck will be demolished and a new deck built on the existing substructure
Eastbound traffic will be diverted onto the new eastbound deck and the original westbound deck will be demolished. The new westbound deck will then be slid into position and carriageway tie-ins completed.
During the course of the scheme some short-term lane closures will take place in both directions at various times. A short-term contraflow will be in operation while the new deck is slid into place. A temporary 50mph speed limit will also be in operation at the works site.
Work on the project will take place between 07:00 BST and 19:00 BST Mondays to Fridays with occasional weekend and nighttime work.