10 ms·

A plan to build a ship tunnel

146 points by omnibrain 10y ago

shaftway 10y ago
Site down: cached at http://webcache.googleusercontent.com/search?q=cache:YX9ObTmWy2EJ:newatlas.com/stad-ship-tunnel-interview-terje-andreassen/48480/+&cd=2&hl=en&ct=clnk&gl=us http://webcache.googleusercontent.com/search?q=cache:YX9ObTm...
205guy 10y ago
Site working again, but headline still false: Built in 1679, 165m long: https://en.wikipedia.org/wiki/Malpas_Tunnel https://en.wikipedia.org/wiki/Malpas_Tunnel Built in 1832, 3333m long: https://en.wikipedia.org/wiki/Canal_de_Bourgogne https://en.wikipedia.org/wiki/Canal_de_Bourgogne Built in 1927, 7120m long: https://en.wikipedia.org/wiki/Rove_Tunnel https://en.wikipedia.org/wiki/Rove_Tunnel The first two are canal tunnels not at sea level, but the last one is connected to the Mediterranean at sea level.
- dang 10y ago
  Ok, we'll s/the world’s first/a/. That is usually a pretty good idea anyhow.
- ryanwaggoner 10y ago
  Maybe those would be considered boat tunnels, not ship tunnels?
  - djsumdog 10y ago
    Yea, none of those seem to match the scale of the proposal in the article.
- Doctor_Fegg 10y ago
  Absolutely. In Britain the trailblazer was the 2633m Harecastle Tunnel, built by James Brindley in the 1770s: https://en.wikipedia.org/wiki/Harecastle_Tunnel https://en.wikipedia.org/wiki/Harecastle_Tunnel . TFA describes the Norwegian tunnel as "the world's first ship tunnel of any significant size", but "significant" changes as engineering advances, and Harecastle was certainly significant at the time - contemporaries thought it an unearthly achievement. Scepticism was such that it was nicknamed an "air castle" (after "castles in the air"). It was the absolute limit of what was believed possible with tunnelling technology through such rock: the 7ft width defined the size of locks and bridges for the rest of the Grand Trunk, or Trent & Mersey, Canal. In turn, this defined the size of the English "narrowboat", the dominant inland craft for cargo carrying and, since the 1960s, pleasure boating. (In modern terms this would be called "boat" rather than "ship", but in contemporary documents it was less clear, and it seems likely that the size was chosen as a half-ship - half the width of the Mersey Flat sailing vessels, on the river with which the canal connected.) The original Harecastle Tunnel is now closed due to subsidence, but the 1820s replacement is still operational, and the rest of the Trent & Mersey Canal is fully navigable and very enjoyable: I moored a boat on it for six years. (For anyone interested in finding out about Britain's 2,500-mile network of historic canals, here's the charity that runs them: https://canalrivertrust.org.uk/ https://canalrivertrust.org.uk/ )
  - tim333 10y ago
    Yeah but it's a bit of a stretch to call that sort of narrow boat a ship http://i.dailymail.co.uk/i/pix/2014/05/21/article-2635127-1E0FF2DE00000578-157_634x420.jpg http://i.dailymail.co.uk/i/pix/2014/05/21/article-2635127-1E...
  - Retric 10y ago
    87 ft is vastly wider than any of those examples. It's the difference between a boat and a Ship. The general definition is a boat is small enough for a ship to carry it. Narrowboat even uses the term boat.
    - Doctor_Fegg 10y ago
      Sure. The point is that this isn't a particularly significant "first" (as the original headline claimed), it's an incremental advance in tunnelling technology. If James Brindley had been able to build Harecastle to Mersey Flat dimensions, he would have done. But tunnels have steadily got broader, deeper, longer and air-draft-ier since Harecastle and Malpas. There was no sudden moment when someone invented and built the ship tunnel. (Incidentally, the "general definition" you cite is one used by the US Naval Institute, but not universally recognised. As the former editor of a monthly news-stand boating magazine it's certainly not one I've ever used. In the UK, for example, you can legally define your small boat as a ship by signing up to the Small Ships Register.)
- sanswork 10y ago
  http://www.penninewaterways.co.uk/tunnels.htm http://www.penninewaterways.co.uk/tunnels.htm There are a lot of canal tunnels in the UK.
mikejmoffitt 10y ago
Asking because I really don't know: How are fluctuations in water level dealt with safely with this sort of thing?
- avar 10y ago
  How much the tide varies in any given area is well-known, you just take that into account when deciding how high to make the ceiling.
  - mnw21cam 10y ago
    Presumably the tide isn't ever sufficiently different on either side of the tunnel to cause a large current through the tunnel.
    - caf 10y ago
      It has a significant east-west displacement so you'd think there would be some tidal flows.
  - jmcdiesel 10y ago
    But a storm surge would be unpredictable, right? How do the physics of "crushing" a boat by raising water level in a confined space work?
    - avar 10y ago
      > But a storm surge would be unpredictable, right? No we know what sort of storm surges are 10, 100, 1000 year events etc. At that point it's just a question of what you design the tunnel to withstand. > How do the physics of "crushing" a boat by > raising water level in a confined space work? This is an elementary application of Archimedes' principle. The weight of the ship is equivalent to the weight of the water it displaces[1]. If the ship is stuck against the ceiling of a confined space the pressure it's excreting on the ceiling is going to be the equivalent to the displacement of that "extra" water. 1. Leaving aside the full calculation which takes the difference in the weight of air & water into account for the purposes of this explanation.
tomohawk 10y ago
If you get a chance, the Paw Paw Tunnel is a great hiking opportunity on the old C&O canal. At 950m, it's pretty impressive. https://en.wikipedia.org/wiki/Paw_Paw_Tunnel https://en.wikipedia.org/wiki/Paw_Paw_Tunnel They actually built this during the days of black powder.
richlj 10y ago
The volume of solid rock removed must be approximately 3 million cubic metres (1700 × 37 × 26.5 x ~2) rather than the 3 billion cubic metres described in the article.
deleted 10y ago
[deleted]
arethuza 10y ago
The Soviets had a neat submarine base that was a curving tunnel through a hill open to sea at both ends - now a museum. Designed to take a 100kt direct hit: https://en.wikipedia.org/wiki/Naval_museum_complex_Balaklava https://en.wikipedia.org/wiki/Naval_museum_complex_Balaklava
- Jaruzel 10y ago
  That's very James-Bondy :)
  - arethuza 10y ago
    Actually, the UK did consider an underground base for its Polaris subs (probably around Lochalsh) but that got ruled out pretty quickly due to the enormous costs. The base also got relocated because the US wanted its UK submarine base to be close to an airport and the UK base ended up being close to the US base at Holy Loch. Which is why the UK has its missile subs based so close to a major city! See: The Silent Deep by James Jinks and Peter Hennessy
matheweis 10y ago
This reminds me of the Magdeburg Water Bridge, which is exactly what it sounds like - a bridge where a canal (big enough for large ships) crosses over a river.

146 points by omnibrain 10y ago

Site down: cached at http://webcache.googleusercontent.com/search?q=cache:YX9ObTmWy2EJ:newatlas.com/stad-ship-tunnel-interview-terje-andreassen/48480/+&cd=2&hl=en&ct=clnk&gl=us http://webcache.googleusercontent.com/search?q=cache:YX9ObTm...

205guy 10y ago

Site working again, but headline still false: Built in 1679, 165m long: https://en.wikipedia.org/wiki/Malpas_Tunnel https://en.wikipedia.org/wiki/Malpas_Tunnel Built in 1832, 3333m long: https://en.wikipedia.org/wiki/Canal_de_Bourgogne https://en.wikipedia.org/wiki/Canal_de_Bourgogne Built in 1927, 7120m long: https://en.wikipedia.org/wiki/Rove_Tunnel https://en.wikipedia.org/wiki/Rove_Tunnel The first two are canal tunnels not at sea level, but the last one is connected to the Mediterranean at sea level.

dang 10y ago
Ok, we'll s/the world’s first/a/. That is usually a pretty good idea anyhow.
ryanwaggoner 10y ago
Maybe those would be considered boat tunnels, not ship tunnels?
- djsumdog 10y ago
  Yea, none of those seem to match the scale of the proposal in the article.
Doctor_Fegg 10y ago
Absolutely. In Britain the trailblazer was the 2633m Harecastle Tunnel, built by James Brindley in the 1770s: https://en.wikipedia.org/wiki/Harecastle_Tunnel https://en.wikipedia.org/wiki/Harecastle_Tunnel . TFA describes the Norwegian tunnel as "the world's first ship tunnel of any significant size", but "significant" changes as engineering advances, and Harecastle was certainly significant at the time - contemporaries thought it an unearthly achievement. Scepticism was such that it was nicknamed an "air castle" (after "castles in the air"). It was the absolute limit of what was believed possible with tunnelling technology through such rock: the 7ft width defined the size of locks and bridges for the rest of the Grand Trunk, or Trent & Mersey, Canal. In turn, this defined the size of the English "narrowboat", the dominant inland craft for cargo carrying and, since the 1960s, pleasure boating. (In modern terms this would be called "boat" rather than "ship", but in contemporary documents it was less clear, and it seems likely that the size was chosen as a half-ship - half the width of the Mersey Flat sailing vessels, on the river with which the canal connected.) The original Harecastle Tunnel is now closed due to subsidence, but the 1820s replacement is still operational, and the rest of the Trent & Mersey Canal is fully navigable and very enjoyable: I moored a boat on it for six years. (For anyone interested in finding out about Britain's 2,500-mile network of historic canals, here's the charity that runs them: https://canalrivertrust.org.uk/ https://canalrivertrust.org.uk/ )
- tim333 10y ago
  Yeah but it's a bit of a stretch to call that sort of narrow boat a ship http://i.dailymail.co.uk/i/pix/2014/05/21/article-2635127-1E0FF2DE00000578-157_634x420.jpg http://i.dailymail.co.uk/i/pix/2014/05/21/article-2635127-1E...
- Retric 10y ago
  87 ft is vastly wider than any of those examples. It's the difference between a boat and a Ship. The general definition is a boat is small enough for a ship to carry it. Narrowboat even uses the term boat.
  - Doctor_Fegg 10y ago
    Sure. The point is that this isn't a particularly significant "first" (as the original headline claimed), it's an incremental advance in tunnelling technology. If James Brindley had been able to build Harecastle to Mersey Flat dimensions, he would have done. But tunnels have steadily got broader, deeper, longer and air-draft-ier since Harecastle and Malpas. There was no sudden moment when someone invented and built the ship tunnel. (Incidentally, the "general definition" you cite is one used by the US Naval Institute, but not universally recognised. As the former editor of a monthly news-stand boating magazine it's certainly not one I've ever used. In the UK, for example, you can legally define your small boat as a ship by signing up to the Small Ships Register.)
sanswork 10y ago
http://www.penninewaterways.co.uk/tunnels.htm http://www.penninewaterways.co.uk/tunnels.htm There are a lot of canal tunnels in the UK.

mikejmoffitt 10y ago

Asking because I really don't know: How are fluctuations in water level dealt with safely with this sort of thing?

avar 10y ago
How much the tide varies in any given area is well-known, you just take that into account when deciding how high to make the ceiling.
- mnw21cam 10y ago
  Presumably the tide isn't ever sufficiently different on either side of the tunnel to cause a large current through the tunnel.
  - caf 10y ago
    It has a significant east-west displacement so you'd think there would be some tidal flows.
- jmcdiesel 10y ago
  But a storm surge would be unpredictable, right? How do the physics of "crushing" a boat by raising water level in a confined space work?
  - avar 10y ago
    > But a storm surge would be unpredictable, right? No we know what sort of storm surges are 10, 100, 1000 year events etc. At that point it's just a question of what you design the tunnel to withstand. > How do the physics of "crushing" a boat by > raising water level in a confined space work? This is an elementary application of Archimedes' principle. The weight of the ship is equivalent to the weight of the water it displaces[1]. If the ship is stuck against the ceiling of a confined space the pressure it's excreting on the ceiling is going to be the equivalent to the displacement of that "extra" water. 1. Leaving aside the full calculation which takes the difference in the weight of air & water into account for the purposes of this explanation.

tomohawk 10y ago

If you get a chance, the Paw Paw Tunnel is a great hiking opportunity on the old C&O canal. At 950m, it's pretty impressive. https://en.wikipedia.org/wiki/Paw_Paw_Tunnel https://en.wikipedia.org/wiki/Paw_Paw_Tunnel They actually built this during the days of black powder.

richlj 10y ago

The volume of solid rock removed must be approximately 3 million cubic metres (1700 × 37 × 26.5 x ~2) rather than the 3 billion cubic metres described in the article.

deleted 10y ago

[deleted]

arethuza 10y ago

The Soviets had a neat submarine base that was a curving tunnel through a hill open to sea at both ends - now a museum. Designed to take a 100kt direct hit: https://en.wikipedia.org/wiki/Naval_museum_complex_Balaklava https://en.wikipedia.org/wiki/Naval_museum_complex_Balaklava

Jaruzel 10y ago
That's very James-Bondy :)
- arethuza 10y ago
  Actually, the UK did consider an underground base for its Polaris subs (probably around Lochalsh) but that got ruled out pretty quickly due to the enormous costs. The base also got relocated because the US wanted its UK submarine base to be close to an airport and the UK base ended up being close to the US base at Holy Loch. Which is why the UK has its missile subs based so close to a major city! See: The Silent Deep by James Jinks and Peter Hennessy

matheweis 10y ago

This reminds me of the Magdeburg Water Bridge, which is exactly what it sounds like - a bridge where a canal (big enough for large ships) crosses over a river.