Say you have completely rigid, undeformable* container that you completely fill with water (no air pockets!), and then cool it to well below freezing. What happens? Can the water turn into ice if it hasn’t any room to expand?
Bonus question: is there any limit to the “strength” of a freezing liquid’s expanding properties? For example, if I were to pump water under a skyscraper and freeze the water, would it be capable of lifting the skyscraper (assuming I properly constrain its sides to prevent outward expansion)?
Squeeze it hard enough, and you can prevent it from freezing. I had a bottle of beer that I put in the freezer to cool down, and when I took it out some time (~1 hour) later, it was very very cold, but still liquid. As soon as I popped the top and relieved the pressure, the beer in the bottle turned to slush over the course of the next twenty seconds or so (a clear bottle, so you could watch the whole thing happen).
I suspect the colder you make the water, the more pressure you need to apply to prevent freezing. I remember a series of still shots where a thick-walled cast-iron vessel was filled with water, sealed, and placed in a pile of dry ice. At some point the vessel shattered. Did I mention that it had thick walls? Cuz it did. Musta been a lot of pressure from the water trying to expand to make that thing crack.
I’m assuming that you’re talking about some sort of perfect indestructible container in the “assume a spherical cow” sense. So, yes, water can indeed be kept at a liquid state well below what we consider its normal freezing temperature. (There’s also the much discussed-here super-cooling, which is a different phenomena) What we think of as normal freezing for water is just the circumstance of existing at this ambient pressure. There’s also not just one kind of ice - when you get into into extremely high pressure, you can also get some fairly exotic crystalline structures forming.
Is this still the theory of how glaciers creep? That the weight of the ice above is enough to squeeze a layer at the bottom back into water, which the ice then slides down on?
One figure I’ve seen says that one tower of the WTC weighed around 500,000 tons. the base of the tower was 208 x 208 feet. If this was a solid slab (it wasn’t), the slab would support (500,000 x 2,000) / 208 x208 x 144 psi or a mere 160 psi. Freezing water can exert over 10,000 psi (some say as much as 100,000 psi), so you could easily lift a skyscraper with the pressure exerted by freezing water.
On a more real-life level rather than the theoretical limits of the performance of some ideal super-material, expanding ice can do serious damage to a rigid container. I’ve put (unintentionally over-filled) Ball glass canning jars of homemade soup or stock into the freezer, and come back later to find the jars broken from the pressure of the freezing liquid.
That wasn’t the question. The question was “would it be capable of lifting a skyscraper”. The answer to that is “yes”, assuming the right conditions. Water is pretty goddamned difficult to compress.
What happens is that the water becomes ice (solid water), but the type of ice it becomes is not Ih or Ic ice, the type of ice formed under ordinary terrestrial conditions. http://www.tms.org/pubs/journals/JOM/9902/Schulson-9902.html
I suspect, but don’t know, that it would be one of the amorphous forms…
“Ice,” which ordinarily is about 9% larger volume than ordinary liquid water, is compressible (as is water) but it takes a lot of force to do so. Expressed the other way around, water being cooled to freezing easily exerts enough force to lift a skyscraper. Enough water over a large enough area would easily push the entire earth around. In practice, a smaller volume of water over a smaller area would just deform that part of the foundation–concrete or steel–since no given component of the foundation is strong enough to lift the skyscraper. But if you floated the skyscraper on a theoretical piston in an water-filled cylinder and froze the water, the skyscraper would easily lift. You could do a rough calculation about how small a volume of water would be needed to lift the skyscraper from the force that water exerts when it freezes.
*"The diagrams show that at -20C, solid ice is ALWAYS the stable phase of
water, so pressure or not, you are guaranteed to have solid ice at -20C.
The “bulk modulus” of ice is about 8.8E9 pascals. You can find that number
on the Internet. “Bulk modulus” is a term that describes how stiff a solid
is. Styrofoam has a small bulk modulus. Rocks have large bulk modulus.
If you completely freeze the ice it expands 9%. If you try to SQUEEZE the
ice back down to the original size, you would need to push with a pressure
of about 790 megapascals of force. (8,800,000,000*0.09) That is about
114,000 pounds per square inch, and is a simple estimate of the pressure
that ice could exert when it freezes, under ideal conditions.
Now, this estimate is not actually correct because in the process of freezing
under pressure, these high pressures can transform the ice into type 3 or 5,
and it is difficult to know what will exactly happen. One can find the bulk
modulus and expansion of ordinary ice, but probably only ice experts know
the bulk modulus and expansion of the other kinds of ice. So I will leave a
perfectly correct calculation up to the ice experts.
In any case, water expands strongly when it freezes, and whether it is
114,000 psi, or 100,000 psi or even 50,000 psi, it can burst pipes and
disrupt foundations."*
**KneadtoKnow’s **answer is the part about “assuming the right conditions”. One of the “right conditions” is a foundation suitable for the water to push against.
I don’t think this is even a minor issue. The compressive strength of concrete is greater than 7,000 psi, and as i showed above, it only takes 160 psi to lift a 108 story skyscraper.
I’m certain that has to do with CO2. Happens to me this time of year because I keep sodas in the garage refrigerator but the inside of the garage freezes. A plastic 2 liter bottle of diet coke will remain liquid until I loosen the top and let CO2 out, and the whole bottle will freeze into slush from the top down, in only a second or two.
However, if you tried filling a 2 liter plastic bottle with uncarbonated water and froze it, the small amount of pressure the bottle could exert on the water wouldn’t lower the freezing point very much.
Is compressive strength the only issue with water and a concrete foundation, though? Doesn’t water pretty commonly find any exploitable defect in concrete and use it to break it apart?
As I said, I’m not an engineer, so I don’t tend to think in terms of ideal structures and merely run the math against them, so I’m sure to be missing that level of abstraction. I’m merely thinking of all the cracked foundations I’ve seen throughout my life.
