I would think that bridges hit by vans would usually be considered safe for continued operations, while those hit by HGV would require much more extensive inspection.
Two lanes of the M6 between J18 and J19 have been closed off for a week, while they are repairing and re-building the cladding of the supports, after an HGV demolished part of it. You can be sure that both motorway and railway were shut for some time, until inspection showed it to be safe enough to re-open the line and part of the motorway.
when I was a student the factory I was at built at 150 ton transformer for the then new Kincardine Power Station (demolished years ago). only about 30 miles, but it had to go by sea since none of the bridges en route over the Forth would take the load.
That is the Network Rail official figure, per strike. However, a delay to trains of two hours does not mean one train stopped for two hours. It is the cumulative total of the delays to all trains crossing that bridge.
The procedure is that all trains will be stopped, pending an inspection. That can be by a Bridge Strike Nominee (BSN); a railway employee who works nearby and who has been trained to assess damage up to a certain level. It the damage is minor enough, the BSN can clear the bridge for traffic. IF not, they have to wait for a full-time Bridge Strike Examiner, which can take quite a bit longer longer. One train will then be cleared to cross at 5mph. If the driver reports no detectable faults in the track, it will be cleared for traffic to cross at 20mph. Full speed will not be permitted until the bridge has been cleared as safe to use. Slow running will usually add to journey times and as trains cross in both directions, it does not take long for the delays to add up, even if the trains are moving.
Probably at reduced speed, pending a full inspection once the vehicle has been removed. OTOH, some are like this:
formatting link
While another bridge was closed for a year to be rebuilt after multiple strikes weakened it too much.
Possibly not when you consider that there is an average of five bridge strikes per day across the network.
HGVs ought to have a sign in the cab (if 3m or taller). Although that doesn't help if there's an oversize load on the back.
The vans which hit the Ely bridge are pretty evenly split between hired, man-with-van and tradesmen. The definition "professional driver" is a little blurred in the latter case, because while a parcel delivery driver most certainly is, I'm not sure a plumber who just happens to have a van, is.
Doesn't take long at Ely. And with most of the vehicles striking it made of nothing more than glass fibre or plywood, and the bridge being a two foot thick reinforced concrete raft, it's a bit of an uneven fight.
Not far away is another, and when that gets struck, the trains stop for longer (maybe three quarters of an hour), and even damage such as pictured here is largely cosmetic (and doesn't get fixed for weeks):
formatting link
Here's a 'wedgie' going the opposite direction:
formatting link
I have no idea where they get that figure from.
Or are old enough to be grandfathered. Planners are usually very pernickety when there's actually a rule needs enforcing.
They have every right to disagree, but that is no reason for the law (Highways Act) to outlaw it. If a Highways Engineer decides it is a suitable solution, then why should the law prohibit it?
The guidelines for surveying bridge heights require measurements of road heights on a 2 metre grid on both sides of the bridge. The high signage is then based upon what height a 25 metre vehicle would require, plus a minimum of 3 inches, to allow for suspension bounce.
In message <shnv4f$dje$ snipped-for-privacy@dont-email.me, at 17:43:57 on Mon, 13 Sep
2021, Steve Walker snipped-for-privacy@walker-family.me.uk> remarked:
The most-bashed bridges (which hence ought to dominate the statistics) are mainly van-munchers. That's why they get bashed over and over again, because it's dimwit white-van-men, rather than lose-their-job-over-it HGVs which are several feet too tall.
The only exception is double decker buses where the driver thinks he's in a single decker. But they are made of plywood too, and don't seem to keep bashing the same bridges over and over again.
Not an overheight-bash then, rather than a straying-across the central reservation bash.
One of the long-tail skewing the average-closure-time, then. Assuming it counts as a bridge bash.
In which case it's an extremely misleading statistic to wheel out in a debate about how long it takes to get a bridge inspected and reopened.
And there's also those bridges with movement sensors, which can add to the available data.
It's right next door to a bridge over the River Ouse, which has a severe permanent speed limit, and all the passenger trains (and most of the freight) stop at the station anyway, whose platforms start a few feet south of the bridge. Therefore the concept of "limited speed" is somewhat muted.
But, and this is the crucial thing, every time the bridge gets hit there's uproar on social media, as if as a result the disruption is catastrophic. Although probably they are more worried about the disruption to cars, which would be much the same if it was a sacrificial beam that was hit, rather than the bridge. Or possibly worse, because then they'd have to send out beam-inspectors to see if it was safe to reopen to traffic, possibly after some temporary repairs to the beam.
That's a typical "difficult case" that doesn't say much about the problem in general, other than perhaps adding tens of thousands of delay minutes to the averaging procees in one go.
It looks like a classic location where a reinforced portal (which would be part of the bridge, and not a sacrificial beam, could in fact be useful. If it gets bashed and closed for repairs, more than say once every couple of years.
That's going to skew the average considerably, if by "closed" you mean to rail traffic. A bit of a leisurely schedule if you don't mind me saying.
Is that reported bridge strikes? Quite a few unreported ones here:
formatting link
I witnessed a very likely unreported bash there (Ely obviously) a couple of years ago, a flat-bed van with various building/gardening equipment/ tools on the back, clipped the bridge by a couple of inches with the handle of one. It simply toppled onto bed. If it had been somersaulted out of the van it could quite likely have been run over by myself, at which point I probably *would* have reported it (and hopefully had the police go have a chat with him later). One of various close-miss scenarios on roads in general, that convinced me to get a dashcam.
Of the five-a-day you mention, I wonder how many are what could be classed as "serious". eg, needing more than deflating the tyres on the vehicle to get things moving again.
In message <shqf5j$8u2$ snipped-for-privacy@dont-email.me, at 16:29:54 on Tue, 14 Sep
2021, Steve Walker snipped-for-privacy@walker-family.me.uk> remarked:
Because that highways engineer who thinks it's a good idea (and probably hasn't fully considered who is going to pay for the installation - including buying the ground on which it's erected - and the maintenance in perpetuity, is the outlier.
Except he's the man on the ground, backed by a team, who can see the actual situation, rather than people centrally who have never seen the location and the particular circumstances.
In message <si2haf$l7k$ snipped-for-privacy@dont-email.me, at 17:55:42 on Fri, 17 Sep
2021, Steve Walker snipped-for-privacy@walker-family.me.uk> remarked:
The people centrally have researched numerous locations, and categorised them. As well as evaluating various styles of sacrificial beam. Then written papers about whether it's helpful to install them. They've done the same for the tiger-stripes, which are commonly deployed, and whose purpose is an optical illusion to make the bridge-hole look smaller, so fewer people try to squeeze under.
I wonder if in fact that isn't slightly "crying wolf", but then I haven't spent years working with the relevant psychologists, and sometimes you just have to believe that experts know what they are talking about.
But does that research say that they are never a good option or just rarely the best? Every situation is different and in some cases, a beam
*may* actually be the best, but if the rules simply prohibit using them for new installations, that would then force a sub-optimal solution.
I am not saying that they should be used, but that they shouldn't simply be ruled out entirely. For instance a road near here has a turn into a junction, with a bridge straight after. Years ago it had poles on chains, lights, stripes, etc., but was still regularly hit. At the time beams were an option, so they fitted a massive pair and they are still there. Probably the best option, considering that the bridge carries the Bridgewater canal, that runs for 41 miles with no locks and therefore any damage could lead to massive damage, as the raised canal drained into the surrounding residential area.
In message <si4m3i$2qt$ snipped-for-privacy@dont-email.me, at 13:29:38 on Sat, 18 Sep
2021, Steve Walker snipped-for-privacy@walker-family.me.uk> remarked:
iirc it says they are rarely cost-effective (which is a different criteria than "a vague "best") .
Road traffic law is like that. Anywhere with streetlights gets a 30mph implied speed limit whether it's optimal or not. Saves having to examine every single installation on its merits.
Well, that didn't work, did it!
But is the beam in any sense "part of the bridge"? If not, on whose land are the posts mounted, and who paid for the beam - BWB or someone else?
I don't know who paid for them, but they are (on the short approach) about 25 to 30 feet from the bridge and (on the other side) 100ft or more away - on that side the road drops for that whole distance and the houses are on raised pavements, with iron railings, so there is no need for taller vehicles to drive on that section.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.