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Ice and aqueducts


G4YVM

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My brother says that if the Pontycyssilt aqueduct iced up it would burst open, destroying it.

It has regularly, and it doesn't!

 

Don't think that has much to do with it being open at the ends though!

 

(I assume you meant Pontcysyllte? You seem to have lost an "e", gained an "i" and maybe an extra "s", and then had a general shuffle!)

Edited by alan_fincher
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I think that layer of ice on the top is not a problem, but freezing solid might be, especially if the ends froze solid before the middle (highly unlikely.). The other factor is the continuous flow of water from Horseshoe falls will tend to reduce the tendency to freeze.

 

N

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Yes although there are plenty of other aqueducts that freeze, without a significant flow, and which still seem to be intact!. The ice can expand upwards, and the cast iron troughs are pretty strong, so no problem. Of course ice isn't rigid, it flows (a la glacier)!

  • Greenie 1
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Ice expands slightly but the cast iron would be able to flex a little if the top layer of ice imparted any sideways forces. So it would not burst. The reason metal pipes can burst if frozen is that they're much smaller cross sectional area, so its possible for much more percentage of that area to freeze solidly, hence greater forces.

 

So in theory, if it got cold enough to solidly freeze the water in the aqueduct, then I suppose its possible to burst it. But I don't think Wales would ever see such harsh conditions to do that (it would need to be a weather extreme such as a polar winter). But then its much thicker than the average pipe. And, its not occurred in the past 200 years or so.

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Yes although there are plenty of other aqueducts that freeze, without a significant flow, and which still seem to be intact!. The ice can expand upwards, and the cast iron troughs are pretty strong, so no problem. Of course ice isn't rigid, it flows (a la glacier)!

I seem to recall that ice was blamed when Marple aqueduct on the Lower Peak burst a wall.

 

Whether this was in the water channel or between the stone joints I cannot say.

 

George ex nb Alton retired

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Ice expands slightly but the cast iron would be able to flex a little if the top layer of ice imparted any sideways forces. So it would not burst. The reason metal pipes can burst if frozen is that they're much smaller cross sectional area, so its possible for much more percentage of that area to freeze solidly, hence greater forces.

 

So in theory, if it got cold enough to solidly freeze the water in the aqueduct, then I suppose its possible to burst it. But I don't think Wales would ever see such harsh conditions to do that (it would need to be a weather extreme such as a polar winter). But then its much thicker than the average pipe. And, its not occurred in the past 200 years or so.

 

But isn't the major difference ice in a small bore pipe is completely enclosed, when it expands it has now where to go once it freezes a long it's length and therefore splits the pipe or pushes off the connectors in some cases.

 

IF the trough on a steel aqueduct froze completely solid surely the resulting hydraulic forces exerted by the expansion would take the path of least resistance ie upwards??

Edited by The Dog House
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Ice expands slightly but the cast iron would be able to flex a little if the top layer of ice imparted any sideways forces. So it would not burst. The reason metal pipes can burst if frozen is that they're much smaller cross sectional area, so its possible for much more percentage of that area to freeze solidly, hence greater forces.

 

So in theory, if it got cold enough to solidly freeze the water in the aqueduct, then I suppose its possible to burst it. But I don't think Wales would ever see such harsh conditions to do that (it would need to be a weather extreme such as a polar winter). But then its much thicker than the average pipe. And, its not occurred in the past 200 years or so.

 

Ice doesn't just expand in every direction. The water slowly increases in volume as ice crystals form, it's a gradual process. It only exerts pressure in a sealed environment.

 

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But isn't the major difference ice in a small bore pipe is completely enclosed, when it expands it has now where to go once it freezes a long it's length and therefore splits the pipe or pushes off the connectors in some cases.

 

IF the trough on a steel aqueduct froze completely solid surely the resulting hydraulic forces exerted by the expansion would take the path of least resistance ie upwards??

 

Yeah possibly, who knows? Its not going to get cold enough to freeze completely, and it seems to cope already with the freezing that occurs in cold winters.

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We had a wooden half barrel water feature in the garden and 2 years ago that froze solid (killed the gold fish) but it didn't split. Just the upper level of the ice was slightly higher than the normal water level.

Therefore i see no reason why the Aquaduct would split.

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Ice expands slightly but the cast iron would be able to flex a little if the top layer of ice imparted any sideways forces. So it would not burst. The reason metal pipes can burst if frozen is that they're much smaller cross sectional area, so its possible for much more percentage of that area to freeze solidly, hence greater forces.

 

So in theory, if it got cold enough to solidly freeze the water in the aqueduct, then I suppose its possible to burst it. But I don't think Wales would ever see such harsh conditions to do that (it would need to be a weather extreme such as a polar winter). But then its much thicker than the average pipe. And, its not occurred in the past 200 years or so.

but it did only 12,000 years ago….

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We had a wooden half barrel water feature in the garden and 2 years ago that froze solid (killed the gold fish) but it didn't split. Just the upper level of the ice was slightly higher than the normal water level.

Therefore i see no reason why the Aquaduct would split.

During my time as a milkman it occurred from time to time that the milk would freeze and this pushed a plug of milk up out of the top of the bottle. People sometimes complained "Hey Milko my milk is frozen" as if I could do anything about the weather. My stock reply was "Yes missus so am I"

 

Phil

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During my time as a milkman it occurred from time to time that the milk would freeze and this pushed a plug of milk up out of the top of the bottle. People sometimes complained "Hey Milko my milk is frozen" as if I could do anything about the weather. My stock reply was "Yes missus so am I"

 

Phil

Did you ever get a warming up offer?

 

Go on, tell us.

 

Edit for typo.

Edited by nb Innisfree
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Thank you all.

 

Sorry for miss-spelling the old girls name too.

 

D

Actually it was for many years known as Pont (bridge) y (the) Cysyllt (connection, link, junction)

I still call it Pontycysyllt as do most other Welsh speakers that I know.

Felly paid a becso! (so don't worry!)

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