How much does it cost to raise a railway bridge?

[saaby93]

With the spate of lorries hitting low bridges


http://www.bbc.co.uk/news/uk-england-44023027
Theyre talking about mounting beams either side that the truck will hit first but how much would they need to raise the bridge and ideally how high does it need to be?
Or can they dig the road lower by about a foot

[gothatway]

Surely it must a lot cheaper to lower the road than to lift, raise and relay the trackbed ? I guess that drainage would be a problem.

[saaby93]

gothatway said:

Surely it must a lot cheaper to lower the road than to lift, raise and relay the trackbed ? I guess that drainage would be a problem.

Opulent Bob in other forums describes eye watering costs by services to be relocated

To run the stupid speed limit argument, the speed limit there may be too low so drivers may be worrying more about that than the height of the bridge.

[valiant]

Raising the bridge ain't going to happen. Costs would indeed be eyewateringly expensive as the gradient for the trains has to be shallow and gradual. You'd be staring you're 'dig' from a fair distance away in either direction depending on what type of trains use it (freight trains especially so). Building anything on the railway is monumentally expensive.

Far cheaper to have a height sensor fitted a few hundred yards from the bridge linked to a set of traffic lights and build a turn around point or escape road if necessary like they have on the Blackwall Tunnel.

Harsher penalties for those who manage to ignore all the above would help sharpen a few minds as well...

Edited by valiant on Tuesday 8th May 11:11

[saaby93]

valiant said:

Raising the bridge ain't going to happen. Costs would indeed be eyewateringly expensive as the gradient for the trains has to be shallow and gradual. You'd be staring you're 'dig' from as much as a mile away in either direction depending on what type of trains use it (freight trains especially so). Building anything on the railway is monumentally expensive.

Far cheaper to have a height sensor fitted a few hundred yards from the bridge linked to a set of traffic lights and build a turn around point or escape road if necessary like they have on the Blackwall Tunnel.

Harsher penalties for those who manage to ignore all the above would help sharpen a few minds as well...

Trouble with penalties is they always kick in after something has happened rather than preventing it and as weve seen with the bus cash gate cash cows there can be an incentive in keeping penalties flowing.
How many penalties do you need before it's cheaper to raise or dig out under the bridge?

Can you say more about the Blackwall tunnel system?

[stevesingo]

I was talking to a truck driver a few months ago and he highlight a problem with resurfacing.

The standard bridge on a trunk road should be 16'6". When the road gets resurfaced, the road rises but no one resets the height signage.

He got a load stuck under a bridge, causing significant damage to the load. the load was a pedestrian bridge for a railway and was always going to be tight, so the driver double checked. His boss turned up and was going to fire him until the police officer pointed out that his laser measure read less than 16'6" clearance between the newly resurfaced road and the underside of the bridge.

[Jader1973]

There is a bridge in South Melbourne that kept getting hit by things.

They’ve put huge dangling gantries either side of it for anything over height to hit before they get to the bridge, although it got hit again a few days ago after quite a while with no issues.

It even has a website

http://howmanydayssincemontaguestreetbridgehasbeen...

[FourWheelDrift]

Probably cheaper to develop and mount a scanner on either side that continuously checks the height of approaching vehicles and then flash up big red STOP lights.

[saaby93]

Jader1973 said:

There is a bridge in South Melbourne that kept getting hit by things.

They’ve put huge dangling gantries either side of it for anything over height to hit before they get to the bridge, although it got hit again a few days ago after quite a while with no issues.

It even has a website

http://howmanydayssincemontaguestreetbridgehasbeen...

3 metres

[Rick101]

FourWheelDrift said:

Probably cheaper to develop and mount a scanner on either side that continuously checks the height of approaching vehicles and then flash up big red STOP lights.

Believe me, that would do little to prevent it.

Always amazes me how many bridge strikes occur and how many signs must have been missed or ignored.

The delays it can cause can be extraordinary.

[shakotan]

http://11foot8.com/

[anonymous-user]

stevesingo said:

I was talking to a truck driver a few months ago and he highlight a problem with resurfacing.

The standard bridge on a trunk road should be 16'6". When the road gets resurfaced, the road rises but no one resets the height signage.

He got a load stuck under a bridge, causing significant damage to the load. the load was a pedestrian bridge for a railway and was always going to be tight, so the driver double checked. His boss turned up and was going to fire him until the police officer pointed out that his laser measure read less than 16'6" clearance between the newly resurfaced road and the underside of the bridge.

You don't resurface directly over the old surface. You remove existing and relay ("inlay") the top 20/30/40mm. Surface dressing adds a millimetre to the height of the road. I have never, EVER relaid on top of old without planing off first. There are lots of reasons why it's a bad idea...

You MAY have to do it (overlay) on a concrete road but very very few roads are concrete nowadays.

[valiant]

saaby93 said:

Trouble with penalties is they always kick in after something has happened rather than preventing it and as weve seen with the bus cash gate cash cows there can be an incentive in keeping penalties flowing.
How many penalties do you need before it's cheaper to raise or dig out under the bridge?

Can you say more about the Blackwall tunnel system?

Pretty simple (although probably hugely expensive!) system.

First off you have normal height warning signs repeatedly set for miles before you approach the tunnel. Then you have alternate route signs for overheight vehicles, again repeated as you get nearer.

As you get near the tunnel, there are hanging metal poles dangling at a set height that if you hit, you are over therefore overheight and you are to use the escape road which will send you back the way you've came from.

Finally, If you miss all the above, as you approach the tunnel itself, a set of traffic lights near the tunnel mouth will turn red if you approach with an overheight vehicle and a tannoy will blare out that you are to use the escape road. Fail to do all this and the police or tunnel recovery crews will come along and tell you to use the escape lane and about a thousand other drivers will be calling you a dhead for holding them up.

It's a bit overkill for the bridge you mention but elements could be used.

Regards to penalties, I'm not so sure i agree with your posting truckers like to think of themselves as professional drivers (and so they should) so should be treated as such and held to account when standards slip and incidents happen. If they know there's a high probability of losing their licence and thus their career, maybe they'll pay more attention?

I'm a train driver. I KNOW that if I fkup badly enough then my job is toast. My feet won't touch the ground in how fast I'll end up on the street and I'll never see the inside of a train cab again, plus I may even be prosecuted if it warrants it. This keeps me focused and attentive to what's going on around me. Maybe truckers should be held to similar standards?

[Rick101]

Whilst I agree with the sentiment, Train drivers have a lot of responsibility and are paid adequately for that risk. You get a certain type of person as a train driver.

Your average van/truck driver is on peanuts in comparison. We all know what happens when you pay peanuts.

[swanny200]

There is a bridge in Strood, Kent. Used to work right next to it, and no matter what they did with it (it had the dover to victoria main line above it), putting low height sensors (which used to conk out religiously), big signs saying low bridge etc... every month something would clout into it, so much so that we had the bridge strike line on speed dial when I worked there. 9ft 3in clearance and road narrowing to a single lane, but still you would see lorries or luton vans try and get under when there were plenty of routes out further up the road.

[aeropilot]

valiant said:

Raising the bridge ain't going to happen. Costs would indeed be eyewateringly expensive as the gradient for the trains has to be shallow and gradual. You'd be staring you're 'dig' from a fair distance away in either direction depending on what type of trains use it (freight trains especially so). Building anything on the railway is monumentally expensive.

Far cheaper to have a height sensor fitted a few hundred yards from the bridge linked to a set of traffic lights and build a turn around point or escape road if necessary like they have on the Blackwall Tunnel.

^This.

[jimbobsimmonds]

swanny200 said:

There is a bridge in Strood, Kent. Used to work right next to it, and no matter what they did with it (it had the dover to victoria main line above it), putting low height sensors (which used to conk out religiously), big signs saying low bridge etc... every month something would clout into it, so much so that we had the bridge strike line on speed dial when I worked there. 9ft 3in clearance and road narrowing to a single lane, but still you would see lorries or luton vans try and get under when there were plenty of routes out further up the road.

Darnley arch, Gun lane or the one by the old Civic Centre car park? R Swains haulage are now located down knight road, so you can imagine the problems you get at Darnley arch with hundreds of artics going through every day...

Unfortunately, not a lot you can do...

[Rick101]

Even if you do raise the height, a higher vehicle will still ignore the signs and end up striking it.

Much like the level crossing conundrum, the only safe one, is a closed one.

[saaby93]

Rick101 said:

Even if you do raise the height, a higher vehicle will still ignore the signs and end up striking it.

Much like the level crossing conundrum, the only safe one, is a closed one.

ha ha good comparison - and then it's not a crossing.
Instead there are many safe crossings how to change operation of the unsafe ones in line with those

So here most bridges are used safely, what is it about the few bridges that trucks seem to miss all the warnings
Is it a Ladbroke Grove situation?
Have the warnings been placed, where they look obvious in photos, but not where youd naturally spot them while driving.
And there will be a height where most if not all vehicles will clear them.

[Gareth1974]

FourWheelDrift said:

Probably cheaper to develop and mount a scanner on either side that continuously checks the height of approaching vehicles and then flash up big red STOP lights.

I often see suggestions such as this. These systems are in use, one is positioned either side of a frequently hit bridge on the A5 near Hinckley, yet the drivers ignore it and smash in the bridge regardless. The bridge also has concrete beams each side to protect it, although if you drive fast enough, you can get under these.