Skew Bridge Lifts Completed
The Bristol Guided Busway project achieved a significant milestone at the end of January when the last of the main steel bridge beams was lifted into place. The Busway runs from Aston Vale Park & Ride to Temple Meads in the centre of the city with 2.7km of new carriageway and is part of a wider integrated transport scheme linking Bristol with Gloucestershire to the north and Somerset to the south. At the centre of the scheme is the Skew Bridge which runs parallel to and then crosses the Portishead railway line.
The bridge is made up of two reinforced earth approach ramps and a 155m long composite deck over five spans. The deck width varies 8.6m to 12m to allow for the unusual skew alignment dictated by the tight planning boundary and is curved in both the vertical and horizontal planes to allow the structure to clear the railway line by 7.2m, allowing for potential future electrification.
The steel beams were fabricated by Victor Buyck Steel Construction at their factory in Ghent, Belgium. Installed as braced pairs for stability, the whole structure is made up of four main girders, each of nine sections which were transported to site for further assembly two weeks prior to erection. As each braced pair was bolted together on trestles adjacent to the bridge site, permanent GRP formwork was fixed along with the RMD paraslim parapet falsework and edge protection was attached to reduce the amount of work at height adjacent to the railway. As the site has limited laydown area, delivery of subsequent sections was dependant of the placement of those beams already on site.
The final 2 pairs of beams were lifted into place on Sunday 29th January and the event was witnessed by the Operations Director and Transport Councillor for Bristol City Council, local press and the BBC.
The completion date for the scheme is July 2017.