alt Hacker NewsGiven the number of cctv cameras that operate in the UK, and their continued growth, I am surprised that the rail operator did not have access to a direct view of the bridge. I am also a bit surprised that there isn't technology to detect rail damage, especially the power lines that runs over the track.
Where I live it is not uncommon for rail to have detection for people walking on the rail, and bridges to have extra protection against jumpers. I wouldn't be that surprised if the same system can be used to verify damage.
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There is technology that could detect rail breaks, in the form of track circuits: feed a current into a rail, detect whether it gets to the other end (or bridge the two rails at the other end of the circuit and see if it gets back to the start of the other rail). A variation of this is commonly used in signalling systems to verify that the track is clear: if a pair of wheels is in the track section then the signal will short across the rails and make the circuit show 'occupied'.
Ultimately, though, this kind of stuff is expensive (semi-bespoke safety-critical equipment every few miles across an enormous network) and doesn't reduce all risks. Landslides don't necessarily break rails (but can cause derailments), embankments and bridges can get washed out but the track remains hanging, and lots of other failure modes.
There are definitely also systems to confirm that the power lines aren't down, but unfortunately the wires can stay up and the track be damaged or vice versa, so proving one doesn't prove the other. CCTV is probably a better bet, but that's still a truly enormous number of cameras, plus running power supplies all along the railway and ensuring a data link, plus monitoring.
This is the part that I find insane. What if the bridge had collapsed, and no one had bothered to post a picture of it to social media?
Contrary to popular belief, not every single square inch of the UK is covered by state operated CCTV.
One of the more interesting ways of detecting rail damage, and subsidence in general, is optically detecting noise / distortion in fiber optic cables. An applied case of observables which are the basis for an evaluative (the "signal") being utilized originally to diagnose possible maintenance issues and then going "hey there, wait a sec, there's a different evaluative we can produce from this exhaust and sell".
> Given the number of cctv cameras that operate in the UK, and their continued growth,
CCTV cameras are mostly in private ownership, those in public ownership are owned by a mass of radically different bodies who will not share access without a minimum of police involvement. Oh and of course - we rarely point the cameras at the bridges (we have so many bridges).
> Where I live it is not uncommon for rail to have detection for people walking on the rail, and bridges to have extra protection against jumpers. I wouldn't be that surprised if the same system can be used to verify damage.
This bridge just carries trains. There is no path for walking on it. Additionally jumping would be very unusual on this kind of bridge; the big suspension bridges attract that behaviour.
You mentioned twice that you are surprised by things which are quite common in the UK. I don't know where you're from, but it's worth noting that the UK has long been used as a bogeyman by American media, and this has intensified recently. You should come and visit, the pound is not so strong at the moment so you'll get a great deal to see our country.