Wednesday 18 June 2014

Work is kicking off in earnest now, with progress on both bridges 1 (Broadway) and 5 (Little Buckland).

Here are the pictures of Broadway, where the road closure took effect on Monday, thus allowing the contractors to start some serious work:

A prop is readied
The main objective at Broadway today was to get 4 supports in under the bridge.




These have a thread under each end, which can be turned until the support is tight under the bridge. They are then also cross braced. The purpose is not to lift the entire bridge up - this could result in distortion, or indeed rupture, as the double track bridge forms one whole element - but to provide replacement support for when the bottom flange is removed for renewal.
This is what the bottom flange looks like:


As you can see, it has been struck at least twice by a pointed object, such as the jib of a JCB or 360. And this was after the 1975 strike, when a large 360 was involved, and a patch was required for the whole web on this side.

Count the bridge strikes!

This view underneath shows at least 6 strikes, from both directions. What is bizarre is that some strikes have been well inside the bridge, probably because it was at first struck on the outer edge, pushed down, and then bounced back for a second go. All this damaged steelwork has to be replaced. The bottom flange will be removed, and to continue supporting the heavy bridge (60tons plus?) the four supports have been put in place. One supposes that most of these collisions took place before the A44 by pass was built.

View from the top.
On top at Broadway, the deck has been completely freed and the end brickwork removed to show the ends of the beams. It is believed that these beam ends have never been painted, from new, as they were hidden behind the brickwork.

The next job at Broadway is to put of scaffolding underneath, sheet the whole structure, and allow the shot blasters to clean up those areas where metal replacement is necessary.

At the end of the day.

The picture above shows the site at the close of play. The 4 supports are in place, the road is now closed, and the foot/bicycle path created on the right. George Law report that passers by reaction has been generally positive - a little inconvenience for a longer term general good. Broadway's bric-a-brac sign stands prominent - we are still open for business! Quite a few cars tuned up today, irrespective of the road closure.


Little Buckland:

Parapets cut down.
At Little Buckland, the moth eaten parapets have been removed. They will be replaced with identical new fabrications.



At the end of the day at Little Buckland bridge, the parapets have gone and the whole bridge is encased in plastic sheeting for shot blasting of metal replacement areas to proceed.

We were saddened to hear today that Laverton bridge, with its new concrete deck, has also now had a bridge strike, by drivers unknown. Is CCTV the answer to finding/deterring future culprits?


3 comments:

  1. Sorry to hear about Laverton Bridge, particularly as it's concrete.

    I think CCTV would be difficult to implement, as you'd need power, cameras, someone to watch them, or collision detectors (?) which might be too sensitive and be set off by passing trains. Wouldn't act as a deterrent as these are accidents, caused by people who can't understand a low bridge sign, and the likely ramifications.

    Perhaps sacrificial steel beam(s) or a steel truss, that would take the impact and deform, or crumple, to reduce the impact, could be fitted outboard of the actual bridge?

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  2. Try submitting a claim to the MIB as the driver is untraced and they may well pay out to repair the damage.

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  3. A height sensor at either end would do it. anything higher than will fit under the bridge sets the sensors off which activates cctv..

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