Old Tweed Bridge Refurbishment
The historic bridge crossing the River Tweed has been the main link between Selkirk and Galashiels for over 140 years. However, due to the bridge falling into a state of disrepair, major refurbishment work was undertaken to stabilise masonry. This involved removing the existing bridge infill and taking down the walls, before rebuilding and installing a concrete saddle cast above the masonry arches. Before waterproofing and resurfacing the road above to complete the bridge refurbishment project.
The scaffolding solution had to provide easy access to the walls and underside, enabling full refurbishment to commence after the bridge suffered flood damage. To accommodate these requirements a fully encapsulated scaffold was erected with no restraint provided by the existing bridge structure. Additional requirements involved installing two runway lifting points spanning the full-bridge length above the parapet wall locations.
The scaffold was independently bridged between supporting temporary steelwork, permitting safe access over the river. Additionally, access to the flood arches was provided around the existing shoring structure and designed to be free-standing. By utilising steel unit beams and buttresses fixed down to the concrete base.
We then erected the 780 mono-pitch roof structure spanning between 450 alloy header beams on either side, before covering with Kedar roof sheets installed within the track system. Lateral restraints introduced via a system of plan bracing provided additional support to the roof, transferring the horizontal loads to lateral cross braces in the outside bays of the independent.