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Post by alpinejohn on May 6, 2016 8:40:51 GMT
Once again the Evening Standard is reporting an impact on the Network Rail/District Line bridge over the A205 in Kew. www.standard.co.uk/news/london/south-circular-crash-busy-road-shuts-after-lorry-hits-bridge-for-second-time-in-three-days-a3241276.htmlAs this road appears to be part of a major route across South London it seems strange that steps have not been taken to physically tackle this bridge, by either raising it or lowering the road, or at the very least rapidly installing a very high profile and fully automatic stand off protection system to ensure that drivers of approaching over height vehicles are visibly and loudly alerted in time to stop and turn back before clouting the bridge. Currently it seems TFL are unwilling to act, yet time after time large vehicles are hitting this bridge causing delays and occasionally chaos on both road and rail routes. OK it seems they got away with it this time - but this is happening far too often, and seems almost inevitable there will eventually be an incident here where a truck carrying a rather more solid load manages to displace the track just as a train is approaching with potentially calamitous consequences. I realise the idea of closing the road or the rail line for several weeks to lower the road surface will cause wails of complaint but surely something which "happens often" and has "potential for severe consequences" should be right at the top of TFL Roads action list.
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Post by John Tuthill on May 6, 2016 9:25:54 GMT
Once again the Evening Standard is reporting an impact on the Network Rail/District Line bridge over the A205 in Kew. www.standard.co.uk/news/london/south-circular-crash-busy-road-shuts-after-lorry-hits-bridge-for-second-time-in-three-days-a3241276.htmlAs this road appears to be part of a major route across South London it seems strange that steps have not been taken to physically tackle this bridge, by either raising it or lowering the road, or at the very least rapidly installing a very high profile and fully automatic stand off protection system to ensure that drivers of approaching over height vehicles are visibly and loudly alerted in time to stop and turn back before clouting the bridge. Currently it seems TFL are unwilling to act, yet time after time large vehicles are hitting this bridge causing delays and occasionally chaos on both road and rail routes. OK it seems they got away with it this time - but this is happening far too often, and seems almost inevitable there will eventually be an incident here where a truck carrying a rather more solid load manages to displace the track just as a train is approaching with potentially calamitous consequences. I realise the idea of closing the road or the rail line for several weeks to lower the road surface will cause wails of complaint but surely something which "happens often" and has "potential for severe consequences" should be right at the top of TFL Roads action list. How long before there are so many crashes against this bridge, that irreparable damage is done? Lowering a road is not a major task, time wise and disruption are another matter. Historically it was done around Battersea & Wandsworth, when single decker trams were replaced with DDs, Queenstown Road being a prime example.
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Post by Chris M on May 6, 2016 9:33:53 GMT
Unfortunately the only guaranteed solutions are to remove the height restriction or to make it physically impossible for vehicles over that height to reach the rail bridge. There is a Network Rail bridge in Tulse Hill that was hit for the 17th time in six months on Wednesday. That bridge has massive warnings on the bridge, fixed and electronic signs on the approach and still lorries hit it. The problem as ever though is who should pay for any bridge replacement? It's not the fault of the railway, and if the bridge is signed correctly it's not the fault of the highway authority (both of whom are facing funding squeezes anyway). Even if the driver's insurance pays out for all the damage and disruption (which I doubt) then there is still no money from that source to fund anything new. Changing the height of the railway would be a massive undertaking, requiring possibly a few miles worth of work on the formation. Lowering the road is likely to be less extensive, but you still have to make sure that you don't undermine the bridge abutments. Either set of works will take months at minimum to plan - longer if any closure of the railway is required. So it's not a quick fix.
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Post by phil on May 6, 2016 17:09:38 GMT
Lowering the road is likely to be less extensive, but you still have to make sure that you don't undermine the bridge abutments. Either set of works will take months at minimum to plan - longer if any closure of the railway is required. So it's not a quick fix. Water mains? Sewer pipes? Gas mains? Electric cables (though those tend to be under pavements) - all may need lowering too so as to maintain sufficient ground cover between them and the road surface. Then there is the 'traffic management costs'* to be factored in. As you say the risk of undermining the abutment foundations is another issue. * At least half the costs of motorway widening projects go on cones signs, average speed cameras, collision barriers to protect the workforce, temporary road surfaces, temporary lane markings, temporary lighting, paying for people / equipment to shuffle everything round every few months to give and take back bits of roadspace as the actual widening work is started / finished.
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Post by brigham on May 6, 2016 17:33:13 GMT
Close the road to vehicles over a certain height. Use a girder in rear of the bridge to enforce the closure.
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Post by suncloud on May 6, 2016 20:07:18 GMT
I think one picture I saw shows a sacrificial girder on this bridge, they certainly are used in other locations. While they do not stop a collision they certainly are a cost effective to mitigate the effect on rail infrastructure and services.
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Post by Chris M on May 6, 2016 21:42:37 GMT
Lowering the road is likely to be less extensive, but you still have to make sure that you don't undermine the bridge abutments. Either set of works will take months at minimum to plan - longer if any closure of the railway is required. So it's not a quick fix. Water mains? Sewer pipes? Gas mains? Electric cables (though those tend to be under pavements) - all may need lowering too so as to maintain sufficient ground cover between them and the road surface. Then there is the 'traffic management costs'* to be factored in. As you say the risk of undermining the abutment foundations is another issue. * At least half the costs of motorway widening projects go on cones signs, average speed cameras, collision barriers to protect the workforce, temporary road surfaces, temporary lane markings, temporary lighting, paying for people / equipment to shuffle everything round every few months to give and take back bits of roadspace as the actual widening work is started / finished. I was meaning extensive in terms of distance affected rather than amount of work that needs doing, gas, water and electric can all cope with gradients far in excess of railways (even vertical sections are possible in some cases). Sewerage pipes I admit to being uncertain about this regard. Your point stands though that lowering the road is not necessarily easier or cheaper than raising the railway. As for traffic management costs, I hadn't realised they were proportionally so high, although not all of that would be needed on a project such as is being discussed here.
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Post by Chris M on May 6, 2016 21:50:55 GMT
I think one picture I saw shows a sacrificial girder on this bridge, they certainly are used in other locations. While they do not stop a collision they certainly are a cost effective to mitigate the effect on rail infrastructure and services. But they don't do anything to reduce the direct or indirect costs of the vehicle (and cargo) recovery* and road closure (and carriageway repair in some cases). A beam positioned some way back from the bridge may in some circumstances though allow easier and speedier recovery and may (depending on local circumstances) still allow a diversionary route for cars (until a van tries to use that route).
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Post by roythebus on May 6, 2016 23:38:14 GMT
That bridge was raised in the 1970s to it current height, it used to be 13'9 if I remember correctly. they railed the bridge and the railway track. When I worked on the DR in the early 1970's the bridge used to get hit every week, and that was before the days of the huge artics we have these days.
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Post by crusty54 on May 7, 2016 7:59:32 GMT
There is a sign just before the northbound Blackwall Tunnel which shows the number of overheight vehicles in the past month
It is usually 40+ despite sensors across the road which illuminate several warning signs and physical barriers before the tunnel
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Post by stapler on May 7, 2016 8:51:34 GMT
I was passing under the Roding Rd bridge just north of Loughton station yesterday, and particularly noted the bridge defenders. They are set about 18 in from the main structure and see off the worst offenders - eg an EOS double decker last year, which was fit to join the Hoho fleet once the defences had done their work, and a brand new Biffa dustcart. This would be a very costly road to lower, because of trunk water mains below the carriageway
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Post by alpinejohn on May 7, 2016 10:15:49 GMT
I was passing under the Roding Rd bridge just north of Loughton station yesterday, and particularly noted the bridge defenders. They are set about 18 in from the main structure and see off the worst offenders - eg an EOS double decker last year, which was fit to join the Hoho fleet once the defences had done their work, and a brand new Biffa dustcart. This would be a very costly road to lower, because of trunk water mains below the carriageway From the broad tenor of several posts on here, there appears to be a general acceptance that on cost/convenience grounds, nothing material is going to be done to remove this evident risk to railway users, at least until there has been a serious loss of life incident. Assuming there is a list somewhere identifying the bridges which are hit most often, it would seem a fair strategy to press for a rolling action plan to remove at least the top 5 most frequent locations within the next 5 years, before moving on to the next 5 etc. I guess the potential for action is really down to politicians, and political pressure felt in response to any injuries, deaths or disruption being caused to road and rail users (including of course train drivers who are possibly most at risk). Hence it seems strange that the rail unions are not visibly pressing Ministers for action on this as forcefully as they seem to be with efforts to remove level crossings. Hey Ho - I guess that's life.
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Post by philthetube on May 7, 2016 13:29:05 GMT
I suspect that disruption is a bigger issue than cost, There is probably a strong financial case for doing the work.
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Post by Chris M on May 7, 2016 14:25:30 GMT
If a low bridge is signed correctly there is no reason why it should be hit. There would be no risk to railway users if lorry drivers knew the height of their vehicle (which AIUI should be marked in the cab) and obeyed the road signs regarding maximum height (on a mainline railway forum there is a thread about this issue where at least one professional lorry driver insists he knows better than the road signs what bridges he can get under*). Why should the railway fare payer (and that is who politicians insist must pay for railway improvements) pay for the actions of lorry drivers who disobey road signs?
I think the only realistic answers are (a) making it physically impossible for an overheight vehcile to hit a bridge; and (b) give any driver disobeying a height restriction sign a fine and points on their license, regardless of whether they physically fit or not.
*Signposted bridge heights are calculated by measuring the height at the lowest point above the road (or pavement if this is not physically segregated) and then rounding down to the nearest multiple of three inches so that there is always at least three inches between the bottom of the bridge and the tallest vehicle legally allowed beneath it.
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Post by rincew1nd on May 7, 2016 15:54:21 GMT
*Signposted bridge heights are calculated by measuring the height at the lowest point above the road (or pavement if this is not physically segregated) and then rounding down to the nearest multiple of three inches so that there is always at least three inches between the bottom of the bridge and the tallest vehicle legally allowed beneath it. Quite. We wanted to take our roller along a road with a height and width restriction, we measured the height of the engine and there was no concerns here. However, when we measured the width it was exactly the same as the restriction. So we thought it should fit, but had they measured the tops of the kerbs, or where they meet the road surface? Well there's only one way to find out! A tight fit by Paul Knapton, on Flickr
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Post by countryman on May 7, 2016 16:12:49 GMT
There would be no risk to railway users if lorry drivers knew the height of their vehicle (which AIUI should be marked in the cab) and obeyed the road signs regarding maximum height (on a mainline railway forum there is a thread about this issue where at least one professional lorry driver insists he knows better than the road signs what bridges he can get under*). This may be true of rigid lorries, but with artics with varying trailers, I have seen this marked on the trailer as the height when attached by a standard height 5th wheel. It would not be appropriate for this to be displayed in the cabs.
I went on a vintage bus running day in Watford and was somewhat surprised when the 14ft 6 inch RT I was on went under a bridge with a 14ft 3 inch warning at Bushey!
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Post by Chris M on May 7, 2016 18:32:19 GMT
Well the bridge height above the highest point underneath could be anywhere between 14' 6" and 14' 9" but still a vehicle in excess of the height restriction should not be passing a height restriction sign. The safety margin is there for a reason!
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Post by phil on May 7, 2016 19:11:38 GMT
I was passing under the Roding Rd bridge just north of Loughton station yesterday, and particularly noted the bridge defenders. They are set about 18 in from the main structure and see off the worst offenders - eg an EOS double decker last year, which was fit to join the Hoho fleet once the defences had done their work, and a brand new Biffa dustcart. This would be a very costly road to lower, because of trunk water mains below the carriageway From the broad tenor of several posts on here, there appears to be a general acceptance that on cost/convenience grounds, nothing material is going to be done to remove this evident risk to railway users, at least until there has been a serious loss of life incident. Assuming there is a list somewhere identifying the bridges which are hit most often, it would seem a fair strategy to press for a rolling action plan to remove at least the top 5 most frequent locations within the next 5 years, before moving on to the next 5 etc. I guess the potential for action is really down to politicians, and political pressure felt in response to any injuries, deaths or disruption being caused to road and rail users (including of course train drivers who are possibly most at risk). Hence it seems strange that the rail unions are not visibly pressing Ministers for action on this as forcefully as they seem to be with efforts to remove level crossings. Hey Ho - I guess that's life. Level crossing pose a FAR higher risk than bridge bashes of people being killed / injured (have a look at the official statistics) and it is absolute nonsense to try and equate the two. The train drivers union position reflects this reality. In any case NR have invested heavily in installing protection beams to the most hit bridges - and while yes trains may well have to be stopped until the bridge is inspected, if the protection beam has done its job train services can be up and running fairly quickly. Bridge bashes are a ROAD TRAFFIC problem and any funding to change the height should come exclusively from the ROADS budget. Height restriction signs are there for a reason and if road hauliers cannot get their drivers to obey them then its not the railways responsibility to fix them. A start would be to massively increase the fines and make dam sure that it hits operators as wlel as drivers in the Wallet - too many big pay outs by the big logistics companies would get the attention of the people who matter in such organisations.
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Post by phil on May 7, 2016 19:17:21 GMT
Well the bridge height above the highest point underneath could be anywhere between 14' 6" and 14' 9" but still a vehicle in excess of the height restriction should not be passing a height restriction sign. The safety margin is there for a reason! Precisely - for example a heavily loaded bus or lorry will naturally have a lower overall height than one that is full. Given this variation and the fact that the marked vehicle heights as displayed in cabs ignore loading factors the measurements on the signs have to include a safety margin. That however does not excuse anyone contravening the sign.
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Post by countryman on May 7, 2016 19:52:36 GMT
I would like to point out that the vehicles concerned were the same as the ones that used to run under the bridge years ago, and presumably the organisers had ensured that there would be no problem!
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Post by Chris M on May 7, 2016 20:00:16 GMT
phil I think you mean "empty" rather than "full" in that post, but yes. The safety margin is also there for things like measurement errors, temperature changes, defects or changes in the road surface, bouncing vehicles or loads, vehicles mounting pavements (deliberately or otherwise), etc - and obviously combinations of any of these. The bottom line is that if your vehicle is equal to or lower than the height displayed on the sign then your vehicle will pass safely beneath the bridge or other obstacle in all reasonably foreseeable circumstances. If your vehicle is higher than the displayed height then you are responsible for any and all damage that occurs. The highway authority, owner of the bridge and any other relevant parties are entitled to claim any costs they incur from you. If your insurance and/or contract of employment covers this (and I would personally double check all the relevant paperwork before attempting it) then you are luckier than imho you deserve to be.
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Post by spsmiler on May 7, 2016 23:02:03 GMT
in addition to warning signs etc why not install automatic traffic lights in front of bridges? Lorry drivers may not understand signage, but they ought to understand red lights!
For the worst bridges a level crossing type boom could lower when the lights are activated.
Simon
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Post by bassmike on May 8, 2016 11:15:01 GMT
Well the bridge height above the highest point underneath could be anywhere between 14' 6" and 14' 9" but still a vehicle in excess of the height restriction should not be passing a height restriction sign. The safety margin is there for a reason! Precisely - for example a heavily loaded bus or lorry will naturally have a lower overall height than one that is full. Given this variation and the fact that the marked vehicle heights as displayed in cabs ignore loading factors the measurements on the signs have to include a safety margin. That however does not excuse anyone contravening the sign. I.S.T.R that some Routemasters were 14'8" over roof vents.
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roythebus
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Post by roythebus on May 8, 2016 13:59:53 GMT
The design height of the Routemaster is 14'2 according to the official LT drawing I have in my collection. The RT is probably the same, the BEA 4RF4 is 11'11" for those who are interested... Modern vehicles usually have air suspension which should maintain a constant ride height, so it matters not whether they are loaded or empty.
LT used to provide a book of all low bridges in the LT area (including the Country area), I think I still have a copy somewhere, and Centrecomm certainly has a list of them. The Centrecomm radio automatically issues a low bridge warning to bus drivers too. There really is no excuse for hitting a bridge.
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Post by John Tuthill on May 8, 2016 15:09:16 GMT
The design height of the Routemaster is 14'2 according to the official LT drawing I have in my collection. The RT is probably the same, the BEA 4RF4 is 11'11" for those who are interested... Modern vehicles usually have air suspension which should maintain a constant ride height, so it matters not whether they are loaded or empty. LT used to provide a book of all low bridges in the LT area (including the Country area), I think I still have a copy somewhere, and Centrecomm certainly has a list of them. The Centrecomm radio automatically issues a low bridge warning to bus drivers too. There really is no excuse for hitting a bridge. I entirely agree. I'd put it down to: a)Saving mileage=money b) Stupidity c)carelessness. I hope the relevant authorities count up the costs sue the relevant parties and splash it all over the relevant web sites/transport magazines etc.
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Post by Tomcakes on May 8, 2016 15:41:11 GMT
The introduction of sat navs can surely not have helped. A huge number of motorists follow blindly what the sat nav tells them even when road signs say different - just look at the number of dodgy minicabs doing super dodgy manouvres in town, as they have not sat any exam and are just going where the machine tells them. A prime example is that if you use a prat-nav to my house from some directions it will direct you to take an unauthorised right turn, some drivers I have seen do this even though it's been pointed out to them that they risk a £60 ticket.
Higher penalties could be introduced (to include consequential loss - e.g. if a line is suspended there is the overtime for drivers, delay-repay refunds to passengers, staff time wasted dealing with the incident, engineers being called out to investigate etc - not to mention the cost of putting right the damage) and mandated by law. I daresay that it would encourage operators to take action.
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Post by roboverground on May 8, 2016 15:52:23 GMT
Whilst common practice on the 'National Network' for a Bridge Examiner to be deployed as either an employee holding 'BSN' competence (Bridge Strike Nominee) or 'BSE' (Bridge Strike Engineer), who attends these incidents on the Tube network ?? Is it Emergency Response Unit staff, Duty Reliability Managers or Network Incident Response Managers ? National Network usually deploys a Mobile Operation Manager (MOM) who holds BSN competence and some track inspection staff also hold the competence, is this something the local station supervisor would attend ??
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Post by trt on May 9, 2016 11:36:50 GMT
Bloody bridges, always going on strike.
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Post by brigham on May 9, 2016 11:54:39 GMT
If the protection beam has been correctly installed, then the operation of trains will not be affected by a 'beam strike'.
The shape of the warning sign is also a factor in apportioning responsibility for a bridge strike. If the sign is triangular, it is a WARNING sign, pointing out the height of an overhead obstruction. If the sign is ROUND, then vehicles over the stated height are PROHIBITED, whether they will pass under or not. Even if the bridge span had been lifted completely away, no over-height vehicle would be permitted to pass such a sign.
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