Titan Posted February 14, 2014 Share Posted February 14, 2014 Just a thought why have the blasted tracks at Dawlish not been replaced by slab track then no probs with ballast washing away know it does not help when underneath washed away. Already discussed in this thread (albeit way back at post #40!). Link to post Share on other sites More sharing options...
RMweb Premium Kris Posted February 14, 2014 RMweb Premium Share Posted February 14, 2014 Live images from Dawlish show that the weather conditions are foul. Big waves pounding the wall, but the containers are holding. Link to post Share on other sites More sharing options...
RMweb Premium Mallard60022 Posted February 14, 2014 RMweb Premium Share Posted February 14, 2014 (edited) It looks very much like a rebuilt Spam. If this gets deleted for being irrelevant then so be it. P Edited February 14, 2014 by Mallard60022 Link to post Share on other sites More sharing options...
Pete 75C Posted February 14, 2014 Share Posted February 14, 2014 (edited) Live images from Dawlish show that the weather conditions are foul. Big waves pounding the wall, but the containers are holding. Yes, I just had a look. The screen grab from the webcam is probably the last decent daylight image today. It also goes some way to explain that non-draining slab track might not be the best idea for this location! Edited February 14, 2014 by Pete_S 3 Link to post Share on other sites More sharing options...
Southernman46 Posted February 14, 2014 Share Posted February 14, 2014 I can remember BR trialling a section of slab track during the late 70's, IIRC near Derby on the main line. I think im correct in saying that the trial was not very successful for one reason or another and it was re-laid with conventional track in the 80's sometime. Anyone know any more? The slab (which formed the Up Slow) with all the various Pandrol fixing layouts for plain line / S&C is still there (albeit will the rails long since removed) around about the 114 - 115 milepost area north of Derby Link to post Share on other sites More sharing options...
RMweb Premium Siberian Snooper Posted February 14, 2014 RMweb Premium Share Posted February 14, 2014 (edited) Spotlight have just shown some footage of the sea breaking over the seawall again. SS ps train services in Cornwall are suspened. Edited February 14, 2014 by Siberian Snooper Link to post Share on other sites More sharing options...
Rods_of_Revolution Posted February 14, 2014 Share Posted February 14, 2014 (edited) Yes, I just had a look. The screen grab from the webcam is probably the last decent daylight image today. It also goes some way to explain that non-draining slab track might not be the best idea for this location! grab01.jpg That's because the Victorian seawall design does nothing to stop overtopping. Modern Concave designs eliminate most overtopping. It's worth noting that slab track is not non-draining either, all such concrete areas have drainage built in (even a simple driveway in front of a house does) and if designed properly it's very effective. Cheers, Jack Edited February 14, 2014 by Rods_of_Revolution 1 Link to post Share on other sites More sharing options...
RMweb Premium Kris Posted February 14, 2014 RMweb Premium Share Posted February 14, 2014 ps train services in Cornwall are suspened. That might have something to do with the amount of water in Penzance station. I've just seen a picture showing the water well over rail head height. Link to post Share on other sites More sharing options...
Pete 75C Posted February 14, 2014 Share Posted February 14, 2014 It's worth noting that slab track is not non-draining either, all such concrete areas have drainage built in (even a simple driveway in front of a house does) and if designed properly it's very effective. Cheers, Jack Point taken, but compare a concrete driveway to a gravel drive. Even if the concrete drive has a drainage channel (which it obviously should), which driveway drains quickest? IMHO, just because slab track is a modern solution, doesn't make it best or even better. Usual disclaimer that not being a civil engineer, I could well be talking out of my a*se, it's just an opinion! Link to post Share on other sites More sharing options...
great central Posted February 14, 2014 Share Posted February 14, 2014 It looks very much like a rebuilt Spam. dawlish.jpg If this gets deleted for being irrelevant then so be it. P The loco I'm 99% certain is a 9F, bet the crew were well pleased to be stopped there. However there could be the odd spamcan washing around in the sea Link to post Share on other sites More sharing options...
Rods_of_Revolution Posted February 14, 2014 Share Posted February 14, 2014 (edited) Point taken, but compare a concrete driveway to a gravel drive. Even if the concrete drive has a drainage channel (which it obviously should), which driveway drains quickest? IMHO, just because slab track is a modern solution, doesn't make it best or even better. Usual disclaimer that not being a civil engineer, I could well be talking out of my a*se, it's just an opinion! The thing to keep in mind is not how quickly the water disappears from view, but the damage it does. Ballast will wash away and the ground below will become saturated with water, which compromises the stability of the ground. Although the water appears to drain quickly through the ballast it's still doing damage, not to mention the ballast will be washed away and the track will shift. It might be that water will be visible on a concrete surface longer, but generally it will fall along a gradient and into a channel and it'll drain back into the sea. It's possible the drainage system will be overwhelmed, but even if that happens water will only collect to the point that it begins to flow over the wall and back into the sea and once the storm abates it'll drain away quickly leaving the track in situ and undamaged (probably the biggest advantage to slab track vs ballast and sleepers). There are concrete quaysides at tidal berths across the globe and the drainage is well managed and effective, there's no reason the seawall couldn't be the same. Whilst working in the field of marine engineering I haven't been involved specifically with designing drainage, but I've been seen enough drawings and specs of such systems to know they are effective. Cheers, Jack Edited February 14, 2014 by Rods_of_Revolution 2 Link to post Share on other sites More sharing options...
Pete 75C Posted February 14, 2014 Share Posted February 14, 2014 (edited) The thing to keep in mind is not how quickly the water disappears from view, but the damage it does. Ballast will wash away and the ground below will become saturated with water, which compromises the stability of the ground. Although the water appears to drain quickly through the ballast it's still doing damage, not to mention the ballast will be washed away and the track will shift. It might be that water will be visible on a concrete surface longer, but generally it will fall along a gradient and into a channel and it'll drain back into the sea. It's possible the drainage system will be overwhelmed, but even if that happens water will only collect to the point that it begins to flow over the wall and back into the sea and once the storm abates it'll drain away quickly leaving the track in situ and undamaged (probably the biggest advantage to slab track vs ballast and sleepers). There are concrete quaysides at tidal berths across the globe and the drainage is well managed and effective, there's no reason the seawall couldn't be the same. Whilst working in the field of marine engineering I haven't been involved specifically with designing drainage, but I've been seen enough drawings and specs of such system to know they are effective. Cheers, Jack That's just a polite way of saying I am talking out of my a*se, isn't it!? Seriously, I'm sure you're right. Pete. Edited February 14, 2014 by Pete_S Link to post Share on other sites More sharing options...
RJS1977 Posted February 14, 2014 Share Posted February 14, 2014 More bad news - it would appear the line of containers has been breached: http://www.itv.com/news/westcountry/update/2014-02-14/dawlish-railway-shipping-containers-breached/ Link to post Share on other sites More sharing options...
Rods_of_Revolution Posted February 14, 2014 Share Posted February 14, 2014 More bad news - it would appear the line of containers has been breached: http://www.itv.com/news/westcountry/update/2014-02-14/dawlish-railway-shipping-containers-breached/ It's not surprising, there's not much to stop the containers shifting under the force of the water. It'll still be better than if they weren't there at all, hopefully not too much hard work will be undone! Regards, Jack Link to post Share on other sites More sharing options...
Glorious NSE Posted February 14, 2014 Share Posted February 14, 2014 Looking at the webcam, and comparing it with the time lapse (up thread links) i'm not sure if in reality it's the boxes have moved, or that another chunk of wall has gone... Link to post Share on other sites More sharing options...
BR(S) Posted February 14, 2014 Share Posted February 14, 2014 If this webcam image was taken tonight, it seems to be calmer and the containers are present: http://www.networkrail.co.uk/timetables-and-travel/storm-damage/dawlish/ Link to post Share on other sites More sharing options...
Vanders Posted February 14, 2014 Share Posted February 14, 2014 If this webcam image was taken tonight, it seems to be calmer and the containers are present: http://www.networkrail.co.uk/timetables-and-travel/storm-damage/dawlish/ Given the current weather conditions, it's highly unlikely that image was taken today. The containers shifting would be bad, another section washing out may be worse. Both are bad. Link to post Share on other sites More sharing options...
Glorious NSE Posted February 14, 2014 Share Posted February 14, 2014 It certainly hasn't been a calm night, although it's calmer now than it was earlier... That image I think was tonight, as some of those containers look seriously bashed about - the possible further breach is the opposite end to that image, i'm sure in the previous images the containers went right across the breach, and it looks to me like the difference is more breach, rather than less containers. Link to post Share on other sites More sharing options...
Glorious NSE Posted February 14, 2014 Share Posted February 14, 2014 (edited) The other link again, the BBC's webcam at the South-west end (so, possible further breach at the near end) http://www.siteeyelive.com/monitor/bbcdawlish/camputerb86.jpg Compare with: http://www.bbc.co.uk/news/uk-26180491 Edited February 14, 2014 by Glorious NSE Link to post Share on other sites More sharing options...
Vanders Posted February 14, 2014 Share Posted February 14, 2014 No you're right, that looks like another 50ft-100ft section of the sea wall has collapsed, maybe even more track dangling in mid-air. That's not good, although not as bad as it could be (say, an entirely new breach & washout in a different section of track). There seem to be a lot of flood lights down there; I hope anyone in an orange jacket nearby is safe and sound. Link to post Share on other sites More sharing options...
Glorious NSE Posted February 14, 2014 Share Posted February 14, 2014 I hope anyone in an orange jacket nearby is safe and sound. Definately! Link to post Share on other sites More sharing options...
Rods_of_Revolution Posted February 14, 2014 Share Posted February 14, 2014 Here's a before/after type GIF, though not perfect as the webcam has been adjusted in the mean time. It looks like a section of wall at the far end has gone and some of the containers have buckled. Cheers, Jack Link to post Share on other sites More sharing options...
Glorious NSE Posted February 14, 2014 Share Posted February 14, 2014 Floodlights now on from that view - some very battered boxes, but still there. Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted February 14, 2014 RMweb Gold Share Posted February 14, 2014 The other link again, the BBC's webcam at the South-west end (so, possible further breach at the near end) http://www.siteeyelive.com/monitor/bbcdawlish/camputerb86.jpg Compare with: http://www.bbc.co.uk/news/uk-26180491 Don't overlook the fact that the video in the lower of those two links shows a stretch of the seawall being demolished - so it obviously won't be there now (presumably done as part of the preparation for the new concrete wall?). Link to post Share on other sites More sharing options...
RMweb Gold 96701 Posted February 14, 2014 RMweb Gold Share Posted February 14, 2014 We'll be at the back of the cue, where we should be ) Is there a billiard table nearby? Coat, got. Door, out of. Link to post Share on other sites More sharing options...
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