Monday 26 September 2016

UPDATED Marlow Bridge Closure

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Wednesday 16th November | Bridge safe to be reopened!

Our inspection and testing of the structure has not identified any significant issues which can be associated with the single overweight articulated lorry crossing the bridge.
We are therefore satisfied the bridge will be safe to be re-opened with the current 3 ton weight limit remaining in place.
Prior to this, we need to repaint the areas where the steel was exposed for the weld testing, and so the bridge will need to remain shut for a short period.
The painting involves a 3 coat system which requires time to cure before we can apply the next coat, and is weather dependent.
Once the painting is complete, we will reinstate the thick timber planking in a number of areas that were also removed for the testing.
We will also be removing the scaffolding from around the Marlow bridge towers now that these refurbishment works are complete.
This is planned for Thurs/Fri this week and Mon/Tues next week.
We expect the bridge will open on Friday 25th November, providing we do not experience long periods of rain or freezing temperatures.

Wednesday 2nd November | Marlow Bridge engineers go waterborne for final tests

With the mist lifting on an autumnal Monday morning (October 31), an inspection barge glided slowly into place beneath Marlow Bridge for the final stage of structural engineering tests.
Engineers, commissioned by Buckinghamshire County Council, have been running stress tests on the suspension bridge since a 37-tonne Lithuanian lorry tried to cross it on September 24.
Last week they ordered the specialist barge with a hydraulic hoist on board to allow ultrasound and magnetic particle tests to continue below the road deck during the coming fortnight.
The engineers need to remove decades of paint layers from the metalwork to expose bare metal for these tests. Before tests started on Monday they worked with the Environment Agency to set up a safety exclusion zone around the barge.
Watching the barge move up river was Transport Cabinet Member Mark Shaw, who welcomed the progress being made with the testing regime.
The analysis report should be completed mid-November. If this recommends replacing sections of the bridge, specially manufactured parts could take up to 12 weeks to make and a further eight weeks to install.
'I'm very grateful for the utmost care our engineers have taken with their tests, which I know is exactly what people would expect of us,' said Mark.
'This bridge is special to Marlow and Bisham, and residents I spoke to as we watched the barge move into position appreciated the measures we've taken to ensure no further damage is caused.'
'We're nearing the final analysis report, and as soon as we're able, we want to get repairs underway to make the bridge safe and secure for vehicles.'
Mark said loss adjusters from the Lithuanian transport company's insurers had been in contact and would cover the cost of repairs.
The bridge remains open to pedestrians and cyclists.

Wednesday 19th October | Inspection barge ordered for further underside testing

Structural engineers running stress tests on Marlow Bridge have ordered a river barge to allow work to continue below the road deck.

Since a 37-tonne lorry tried to cross the bridge on September 24, engineers commissioned by Buckinghamshire County Council, have been examining every part of the structure.

This week (w/b October 17) it became clear that seven areas of concern, identified by ultrasound and magnetic particle tests, would need more focused testing to establish whether suspension hangers need replacing.

In the coming two weeks, bare steel will need to be exposed for these tests. Above the road deck engineers are building an access platform, but below the deck a river barge has been requested to allow more intense testing of the highlighted areas on underside of the bridge.

Contract Director Simon Dando said these more focused tests could be carried out only by removing decades of paintwork from the suspension bridge's metalwork, and that engineers were working with the Environment Agency to cordon off a safety exclusion zone around the barge.

Above deck tests will be carried out during half term holiday week (w/b October 24), while engineers will use the barge to access the underside of the bridge the following week (w/b October 31). They will analyse their findings during the first week in November.

If they recommend replacing sections of the bridge, specially manufactured parts could take up to 12 weeks to make and a further eight weeks to install.

Mark Shaw, Buckinghamshire County Council Cabinet Member for Transport said: 'We're taking the utmost care with our testing, which I know is exactly what residents and businesspeople in Marlow and Bisham would expect of us.

'I'm sorry that we need to close the bridge to vehicles, but the risks to engineers' safety, not to mention the potential of additional damage to the structure, make it imperative that we keep it clear of traffic until we know the extent of damage and what repairs are needed.'

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Wednesday 12th October | Marlow Bridge tests reveal more areas for detailed testing

Engineers investigating possible damage to Marlow Bridge, after a 37-tonne lorry tried to cross it, have found seven structural areas that need further detailed testing.
Ultrasound testing and magnetic particle inspections were commissioned by Buckinghamshire County Council earlier this week (w/b October 10) for detailed examination of the suspension bridge's vertical steel hangers.
Testing will continue next week and structural engineers plan to build a small access platform to enable them to more closely examine the bridge steelwork.
Once analysed, the results will reveal whether or not the suspect steel hangers and pins need to be removed for further testing or replacement.
Engineers have been examining every part of the structure since the lorry, owned by the Lithuanian haulage company Girteka, tried to cross the bridge on Saturday September 24. The bridge has a three-tonne weight limit and has been closed to vehicles since, although open to pedestrians and cyclists.
Contract Director Simon Dando said that if the test results clearly showed steelwork needed replacing, specially manufactured parts could take up to 12 weeks to make and a further eight weeks to install.
Mark Shaw, Cabinet Member for Transport, said: 'We're not at this point yet, and we're still undertaking exhaustive tests. But we need to be realistic about a worst case scenario to keep residents and traders in Marlow and Bisham in the picture.
'I appreciate the inconvenience of this closure, and I'm sorry it's needed. We want the bridge open to vehicles as soon as possible, but we must be absolutely sure that it's safe and secure for those who use it.'
County Council officers are researching techniques used by errant lorry drivers to get through width restrictions, to see whether additional measures should be considered for Marlow Bridge.

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Wednesday 5th October | 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 to have 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 involve ultrasound and magnetic particle inspections on the bridge's suspect vertical 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 understand the inconvenience this means for 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 working on these exhaustive tests, which will take some time, and I'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.






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Monday 26th September | Marlow Bridge is closed due to an incident yesterday, Sunday 25th September, involving an HGV.


The inspection is still ongoing but initial findings show evidence of overstressing on key structural parts of the bridge (the abutment bearing and on the steel hangers from the chain).

Based on these initial findings, for safety reasons the bridge will remained closed while further specialist testing/investigation is completed, so we can fully understand the extent of damage caused by the HGV.

We are happy that the footway on one side remains open to pedestrians and cyclists.


Until a full investigation is completed, we will be unable to assess the damage and how long the bridge may need to remain closed to traffic.