trisonic Posted February 23, 2014 Share Posted February 23, 2014 (edited) Good Lord! It appears I was right(ish) about the vertical tubes... I'll admit I'm not smart - but that's what they looked like and made sense. Enjoy the pasty Cap'n.... I still cannot find halfway decent ones over here amongst the philistines... The thing is when you cannot find something on a whole continent you tend to get obsessive about it. Best, Pete. Edited February 23, 2014 by trisonic Link to post Share on other sites More sharing options...
Pete 75C Posted February 23, 2014 Share Posted February 23, 2014 Thanks CK - that should end any speculation! "And certainly not least... fix the damage in all the other locations - the amount of sheer work necessary elsewhere to allow train to start running should not be underestimated, it's not just about the main washout site." Very good point. I think we sometimes forget it's not just about what we can see on the webcam. Thanks for the update and I'm sure we all wish you well. My lunchtime pasty has just defrosted having originated in the Reduced aisle at Tesco, so not at all jealous... Link to post Share on other sites More sharing options...
RMweb Gold Captain Kernow Posted February 23, 2014 RMweb Gold Share Posted February 23, 2014 Is the wall being put back as before or will the path be raised to the level it is along the rest of the section, thus thickening the wall? No, not for now, got to bear in mind that the structure has protected status, so we can't just alter the design without going through the appropriate processes. In the future, however, I'd certainly support doing that, and have already raised it with the relevant engineers. 3 Link to post Share on other sites More sharing options...
Coombe Barton Posted February 23, 2014 Share Posted February 23, 2014 (edited) - Face the outer wall off with granite that matches what Brunel used (our contractors are checking out local quarries at the moment There's a quite attractive wall in front of the harbourside houses in Porthleven. It's white feldspar granite from Merrivale, between Tavistock and Princetown. It should be white, However a few pink feldspar bits have crept in - they're Shap granite. Shap is shipped from Cumbria to Devon to be cut and a few bits must have "missed". The wall at Porthleven looks a bit incongruous and has been the subject of a more then a few of my field trips asking people "what heppened?". Shap is a very distinctive granite and had been extensively studied, not the least by an Open University Senior Lecturer (now retired) who is resident near Fowey. There is almost an atlas of the use of Shap in the UK. Just hope that they can restore the appearance and not have the 'odd bits' thrown at them. Trouble is there's precious few quarries still operating. Edited February 23, 2014 by Coombe Barton Link to post Share on other sites More sharing options...
Pete 75C Posted February 23, 2014 Share Posted February 23, 2014 (edited) There's half a dozen granite quarries still operating in Devon and Cornwall (at least) so hopefully a decent match shouldn't be too much of an issue. I remember reading that the limestone for the sea wall came from Babbacombe near Torquay and the granite came from Haytor Quarry (long gone) via Ventiford and then barge to the Teign. Edited February 23, 2014 by Pete_S Link to post Share on other sites More sharing options...
Coombe Barton Posted February 23, 2014 Share Posted February 23, 2014 There's half a dozen granite quarries still operating in Devon and Cornwall (at least) so hopefully a decent match shouldn't be too much of an issue. As opposed to the hundreds operating previously. There is a hell of an issue. Granites, even in the south west batholith, vary immensely in both crystal size and colour, the mineral composition, the mineralogy, the geochemistry and so on. There's people of my acquaintance who can recognise a granite as coming from from a particular quarry, The granite was not all emplaced at once, and, even more significant, was not formed from the same mix of source rock. This was 300 million years ago, so there's no going back now Rock matching is a fairly exact science - you not only need to look at the appearance, you also need to look at the porosity and weathering properties. (and yes, some granites are porous - just ask the architect of a London skyscraper why there were damp patches on the 30th floor when they didn't have any damp proof membrane but relied on the granite.) The differing mineralogies can be another problem affecting weathering, and the source may have started kaolinisation of the feldspars which will weaken the crystal structure. It's more complex than just colour. Link to post Share on other sites More sharing options...
Pete 75C Posted February 23, 2014 Share Posted February 23, 2014 (edited) Fair point, but I think in this case, a "close match" will suffice. The wall may have a protected status but the bottom line is that it forms part of a vital transport link. Economic issues are surely more important here. It's not some pretty listed folly on a hilltop. Any delay to the reopening of the line whilst a "perfect" match is sought (maybe without success) is something I doubt will be tolerated. Edited February 23, 2014 by Pete_S Link to post Share on other sites More sharing options...
Coombe Barton Posted February 23, 2014 Share Posted February 23, 2014 Fair point, but I think in this case, a "close match" will suffice. The wall may have a protected status but the bottom line is that it forms part of a vital transport link. Economic issues are surely more important here. It's not some pretty listed folly on a hilltop. Any delay to the reopening of the line whilst a "perfect" match is sought (maybe without success) is something I doubt will be tolerated. But it's also about structural integrity and longevity. I'm not suggesting that is should (or even can) be a perfect match colour wise, but needs to last. And NR are going to be blamed if they change the appearance of the pretty seafront. CK has already mentioned that the full height walkway cannot just be restored. Link to post Share on other sites More sharing options...
Gruffalo Posted February 23, 2014 Share Posted February 23, 2014 (edited) I believe that the good Captain was suggesting that the whole section will be made active before a final solution to the wall was applied. This addresses the economic requirement whilst it allows the careful and proper later restitution of the wall to something akin to original colours etc - whilst I do hope the final solution is in such a form as the redirect the force of nature back upon itself - dissipating wave energy rather than trying to absorb it in the structure. Edit: Whilst typing this LBM and CM have almost made surplus my comment. Edited February 23, 2014 by Gruffalo Link to post Share on other sites More sharing options...
RMweb Premium Siberian Snooper Posted February 23, 2014 RMweb Premium Share Posted February 23, 2014 (edited) If enough rock is required to rebuild or repair historical buildings or structures and the original quarry is shut, it's not unheard of to re-open a quarry on a temporary basis to get the required matching stone, unless of course it has been totally worked out. SS edit to make more sense Edited February 23, 2014 by Siberian Snooper Link to post Share on other sites More sharing options...
RMweb Premium Gary H Posted February 23, 2014 RMweb Premium Share Posted February 23, 2014 - The mode of construction (for those who haven't already worked this out) is to place a row of pre-cast concrete blocks along the outer edge, right next to the metal containers. - You then drill them horizontally and insert very long stainless steel anchor pins (these anchor the pre-cast blocks to the concrete that will be poured next) Ah ha! That would explain what a team of diamond drillers were upto in the Dawlish Warren compound when I was there shifting ballast week before last! They had a few dozen of those large reinforced concrete barriers there all laid out on the deck, on their sides having holes bored through them. These are the same things we see used as temporary barriers on motorway's etc! A round 3 tons each. Do the job nicely I should imagine! Link to post Share on other sites More sharing options...
Coombe Barton Posted February 23, 2014 Share Posted February 23, 2014 If enough rock is required to rebuild or repair historical buildings or structures and the original quarry is shut, it's not unheard of to re-open a quarry on a temporary basis to get the required matching stone, unless of course it has been totally worked out. SS I'm thinking that it's likely that it's likely that the original source is now in the National Park which is adding to the complications. Link to post Share on other sites More sharing options...
RMweb Premium petethemole Posted February 23, 2014 RMweb Premium Share Posted February 23, 2014 I really can't see the quarry at Hay Tor being reopened. But I believe that if it were, the NP authorities should require the granite to be transported in the appropriate manner, via the Haytor Granite Tramway. Pete 2 Link to post Share on other sites More sharing options...
RMweb Premium Gary H Posted February 23, 2014 RMweb Premium Share Posted February 23, 2014 And certainly not least... fix the damage in all the other locations - the amount of sheer work necessary elsewhere to allow train to start running should not be underestimated, it's not just about the main washout site. Indeed. I'd wager there are a few places that still look like this- Link to post Share on other sites More sharing options...
Coombe Barton Posted February 23, 2014 Share Posted February 23, 2014 (edited) But I believe that if it were, the NP authorities should require the granite to be transported in the appropriate manner, via the Haytor Granite Tramway. Pete Enter the new tourist attraction - Extreme Railway Preservation Edited February 23, 2014 by Coombe Barton 4 Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted February 23, 2014 RMweb Gold Share Posted February 23, 2014 (edited) Good Lord! It appears I was right(ish) about the vertical tubes... I'll admit I'm not smart - but that's what they looked like and made sense. Enjoy the pasty Cap'n.... I still cannot find halfway decent ones over here amongst the philistines... The thing is when you cannot find something on a whole continent you tend to get obsessive about it. Best, Pete. You and me both Pete (although it did seem rather obvious to be honest that they didn't involve anything solid going down into the bedrock beneath). Ah, pasties - just over a week now that we had some of Mrs Stationmaster's homemade ones - which were greatly enjoyed by all including our visitor from Cornwall. But it's also about structural integrity and longevity. I'm not suggesting that is should (or even can) be a perfect match colour wise, but needs to last. And NR are going to be blamed if they change the appearance of the pretty seafront. CK has already mentioned that the full height walkway cannot just be restored. Let us not forget that the existing 'pretty seafront' owes its entire appearance to the presence of the railway and that it has changed over time and will no doubt continue to change as engineers evolve better methods of protection from a sea - which as we have seen recently - is as much a threat to Dawlish itself as to the railway which protects it. And on a related subject I am reminded of the recent rather stupid tv questioning of Robin Gisby about the cost of the work - the simple answer has of course to be one of emerging cost because notwithstanding estimates what will happen is at the mercy of nature. And all I will add to that is that even well planned schemes on the railway can go awry - the very precisely planned and rapidly implemented conversion of gauge on this stretch in 1892 in fact went over budget and additional funds had to be voted subsequently to pay the costs of items not covered by the original budget. Edit to correct typo Edited February 23, 2014 by The Stationmaster 1 Link to post Share on other sites More sharing options...
yorkie_pudd Posted February 23, 2014 Share Posted February 23, 2014 latest screen pic and funny how one doesn`t notice the containers anymore as almost out of view as rebuilding goes on. Link to post Share on other sites More sharing options...
RMweb Gold Captain Kernow Posted February 23, 2014 RMweb Gold Share Posted February 23, 2014 But it's also about structural integrity and longevity. I'm not suggesting that is should (or even can) be a perfect match colour wise, but needs to last. And NR are going to be blamed if they change the appearance of the pretty seafront. CK has already mentioned that the full height walkway cannot just be restored. I think that NR would be able to demonstrate that all reasonable endeavours had been gone through, in terms of matching the granite appearance. The root cause of the problem is easily enough laid at the door of Mother Nature. It's not a question of changing the configuration of the low-level walkway at this point, although I'd prefer to see it rebuilt to match the existing higher level walkway on the rest of the Sea Wall - we're simply putting it back like it was before the storms. Then the whole debate about new Sea Walls, verses alternative inland routes, can carry on... 3 Link to post Share on other sites More sharing options...
Coombe Barton Posted February 23, 2014 Share Posted February 23, 2014 (edited) I think that NR would be able to demonstrate that all reasonable endeavours had been gone through, in terms of matching the granite appearance. The root cause of the problem is easily enough laid at the door of Mother Nature. And when it comes to it, if there's precious little choice left, it'll be down to the structural properties of the available stone. Edited February 23, 2014 by Coombe Barton Link to post Share on other sites More sharing options...
RMweb Gold Dagworth Posted February 23, 2014 RMweb Gold Share Posted February 23, 2014 Gosh, they really are working their socks off aren't they! Surprisingly, the seaside legs of the concrete pump (or spidery thingy ) are covered in protective material, but the landward side legs, only a few yards further from the sea, aren't... [edit: as I understand it (thx Tim!) the new wall will have a concrete structural core and sandstone decoration. That means that the sandstone is no longer used structurally and it's properties in that field have become much less important. Added benefit is that NR needs less sandstone, hence cutting costs (excuse the pun ) ] Are the covers to protect the machine from the sea or from the concrete it is pumping? Andi 1 Link to post Share on other sites More sharing options...
RJS1977 Posted February 23, 2014 Share Posted February 23, 2014 Thanks CK - that should end any speculation! "And certainly not least... fix the damage in all the other locations - the amount of sheer work necessary elsewhere to allow train to start running should not be underestimated, it's not just about the main washout site." Very good point. I think we sometimes forget it's not just about what we can see on the webcam. Thanks for the update and I'm sure we all wish you well. My lunchtime pasty has just defrosted having originated in the Reduced aisle at Tesco, so not at all jealous... Though presumably some of that work has been ongoing at the same time as the main works on the webcam (one of CK's earlier posts seemed to indicate a second concrete pump in action south of the station). Link to post Share on other sites More sharing options...
bodmin16 Posted February 23, 2014 Share Posted February 23, 2014 And regarding the helmets, this is indeed to do with the way the site has been classified, so all is well and to be expected in that regard. Please note I was not inferring that all was not right with regard to helmet colours, this was a genuine question of interest and I apologise if it could have been misunderstood as any form of criticism. Thanks for all the information and constant updates. 1 Link to post Share on other sites More sharing options...
Keith George Posted February 23, 2014 Share Posted February 23, 2014 How much higher as the concrete infill got to go.? Are the top of the containers lower than rail height. ? Keith. Link to post Share on other sites More sharing options...
RMweb Gold Captain Kernow Posted February 23, 2014 RMweb Gold Share Posted February 23, 2014 How much higher as the concrete infill got to go.? Are the top of the containers lower than rail height. ? Keith. Yes, the tops of the containers are some way below rail height... Link to post Share on other sites More sharing options...
Ron Ron Ron Posted February 23, 2014 Share Posted February 23, 2014 ....... (one of CK's earlier posts seemed to indicate a second concrete pump in action south of the station). Not "seem to indicate", but actually showed another pump in action. Here. How much higher as the concrete infill got to go.? Are the top of the containers lower than rail height. ? See Here. . Link to post Share on other sites More sharing options...
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