We have seen some Big icicules hanging on buildings.
How big would one have to be to really injure someone if it hit them?
Apparently a microwave sized chunk will do you in.
Time for an Icicle Brigade maybe.
Presumably from high enough up a chunk of ice wouldn’t have to be that big if it hit you in the wrong spot.
<hijack=slight>
Pretty icicles hanging from a building, especially long ones, are a sign of poor insulation.
</hijack>
Going on estimates…
My maternal grandparents eaves are @10 feet from the sidewalk.
My 8-year-old cousin was @3’8".
The icicle was @2" in diameter and @18" long.
It gave him a bloody nose, two black eyes, and a concussion.
I’m gonna let the physicists figure that one out…
This is actually a big problem in my neck of the woods. In the Swedish capital, icicles as long as two meters (6.5 feet) are formed each winter. We’re basically talking about humansized spears able to skewer anything. Often, they’re formed under eaves overhanging pavements, and people are seen walking in the middle of the street to avoid getting hit by one. Last winter, an old lady was hit by a 3-foot icicle and had to be hospitalized (I believe she survived but am not sure), which made people demand an Icicle Brigade. We’ll have to see what happens this winter.
Not to mention the boy who got killed by a dropping icicle last winter.
I KNEW there was another incident where the victim died! I just couldn’t remember the details or even who the victim was. This was it, yes. And that was why the demand for an Icicle Brigade grew explosively.
I remember photographs in a debate article of one particular 7-foot icicle hanging right over a heavily trafficked stretch of pavement. The article said a pedestrian had been hit by a car since he used the street to avoid the danger of the falling icicle, and demanded that icicles be removed.
Australians reading this must feel like I do when I read about the redback spider…
My WAG is that, although falling blocks of ice can obviously be dangerous, the probability of an icicle becoming detached and falling intact in such a way as to spear something below must be pretty slim.
And yet it happens. The way I see it, when a spear-shaped icicle starts to thaw, the most likely way for it to detach is in such a way that it does indeed remain intact.
Let’s say the icicle’s diameter and density is such that it weighs one pound per foot, for ease of calculation. Let’s also say it’s 6 feet long. The point one foot from its end has a force of 1 pound exerted on it, the point two feet from the end has a force of 2 pounds exerted on it and so on. Thus the most likely spot to break first is the one at the very top, since it bears the most weight.
If you mean that it should rotate while falling so that it doesn’t land point-first, I disagree with that too. Why would it?
I haven’t studied much physics in my time, so feel free to correct me if I’ve got something wrong.
Oh, and what in the name of the tender mercies of Jesus does WAG mean? I’ve realized that the G stands for Guess, but what’s the rest?
WAG = W(ide) A(rea) G(uess).
And, Mangetout, you should see the Stockholm pavements in wintertime. There are loads of ex icicles on them.
My guess was based on the idea that when it breaks at the top (the thickest part), the break would not be instantaneous, but would be a crack that starts at one side and propagates across the width, not that ice is elastic enough that the icicle could ever ‘hang by a thread’, but if one side breaks away sooner than the other, this should impart some sort of force that would tend to cause rotation during the fall.
Certainly I wasn’t suggesting that the heavier end would fall faster in this case.
But do they fall straight down like a spear or do they tend to rotate or break up as they descend?
[QUOTE]
*Originally posted by Floater *
**WAG = W(ide) A(rea) G(uess).
[QUOTE]
You Swedes are too nice. WAG = wild ass guess. Thats what I say. Others may differ.
How does the Icecicle patroll work? How do they take them down?
The ones in Moscow apparently clear the pavement below, climb up and knock them down. I don’t think they ever got the project going in Stockholm last winter.
They snap and fall straight down onto unsuspecting pedestrians. And as it’s the really big ones that do it the results can be quite nasty. BTW I think I have to correct myself a bit. The boy that was killed was not hit by an icicle. It was an ice flake that fell from a roof. The result, however, was similar.
They get them going every winter as the house owners risk hefty fines if they don’t clear ice and snow away from the roofs and gutters.
Then what was all the hubbub about last winter? Why all the demands for removal of icicles, if they’re routinely removed each winter?
Being forced to do it and actually doing it are two separate things. The problem is that there aren’t enough people around that are willing to get up on slippery roofs and clear the snow away after a blizzard.