Structural survey concern for Marlow Bridge supports

Structural surveyors, inspecting Marlow Bridge during the past week, have found supports above and beneath the road surface that are likely tohave been’significantly overstressed’ and have recommended further tests.

Their inspection followed an attempt on Saturday September 24 by the driver of a 37-tonne lorry to drive across the bridge, which has a three-tonne load limit and width restrictions.

Resonance hammer tests and further visual inspections identified three areas above and below the bridge deck that are giving cause for concern, and engineers say more detailed investigation must be done.

Contract Director Simon Dando said: ‘The results of our tests showed some of the bridge components didn’t ring true, and our key concern is the risk of failure through metal fatigue.’

Further investigation, expected to start later this week (w/b October 3), will involveultrasound and magnetic particle inspections on the bridge’s suspectvertical hangers and pins.Analysis from these tests will be known later next week (w/b October 10).

From the analysis engineers will know whether they need to remove these bridge parts for further testing, and results from these could be available within a month.

Mark Shaw, Buckinghamshire County Council’s Transport Cabinet Member said: ‘I do understandthe inconvenience this meansfor our residents and businesses, but I do know that nothing less than the most stringent of tests and analysis would be expected of us so that we’re absolutely certain about the repairs needed to get the bridge back into a safe working order.

‘We’ve got highly experienced engineers workingon these exhaustive tests, whichwill take some time, andI’m very sorry for the inconvenience. We’re aiming to get the bridge open to vehicles as soon as possible, but my chief concerns are the safety and security of those who use it.’

While tests are being done the bridge will be kept open to pedestrians and cyclists.

The lorry, owned by the Lithuanian haulage company Girteka, approached the bridge from the Berkshire side, damaged its wheels on the traffic calming equipment, before attempting to cross the bridge.

Mark said he had spoken with the company, which had given an unreserved apology, and assured him its insurance would cover repair costs.