Leighton Buzzard Footbridge

THE BRIEF
A pedestrian footbridge, originally built in the late 1800’s, had been identified as unsafe and was closed to the public in January 2019.
Robert West engineers were commissioned by Leeke Associates (lead designers for the scheme) to undertake the Temporary Works design for the removal of the bridge in a similar way to that shown in our video of the removal of Oxford Road footbridge.
The footbridge provided pedestrians and cyclists with a method of crossing from one side of the railway line to the other. Our Transport Planners are undertaking a feasibility study to identify the effect of the removal of the bridge for members of the public.
VALUE-ADDED SOLUTION
The engineering team reviewed historic documentation, undertook site visits, pieced the information together and undertook calculations to assess how the aged structure will change and behave when it is lifted out by crane.
In their investigations the team found that the construction of the footbridge had evolved over the years having been raised to accommodate the electrification of the lines and is made up of three adjoining spans of approximately 24, 14 and 13 metres. It is made of wrought iron and weighs approximately 65 tons in total.
In preparation for the sequencing of the removal of the bridge the team also considered the constraints of the electrified overhead lines, lifting over two sets of railway tracks, train platform and a multi-storey car park. They have designed a temporary structure for the crane and identified the safest order and points at which to cut the bridge.
Meanwhile the Transport Planning team are carrying out a feasibility study to assess the impact of the removal of the footbridge on its users and whether using the footbridge at the Station itself provides a suitable alternative. The footbridge at the Station has turns and handrail separation unlike the footbridge which will be demolished. Work is underway to evaluate any potential impact and to suggest actions to mitigate any negative impact for pedestrians, cyclists and disabled users.
FINAL OUTCOMES
The team have enjoyed providing a multi-disciplinary service to overcome the technical challenges of the engineering analysis and the ‘what if?’ thought processes. Robert West worked closely with Leeke Associates who were responsible for overall design coordination and the geotechnical design for the scheme.
Robert West have responded swiftly to the needs of this project, have been proactive in their communication with the client, issuing draft information where possible to help meet deadlines. The bridge was successfully and safely removed in a 28 hour possession over the early May bank holiday.