Thaw of the Ice

Why don't you tell us what the title of the article was, if it really exists.

Freezing water expands. Thawing ice turns into water.

GA lynlych!

Thawing ice expands a tremendous amount and exerts a lot of force on any structure. There are several USACE Engineering Manuals (EM) on the subject, mostly based on research done at the US Army's Cold Weather Research Center located in the state of New Hampshire.

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In case icicles partly melt and come crashing down onto lower parts of the structure. This would be of interest in cooling towers or evaporative condensers, for instance

When the ice melts at McMurdo station one has to worry about the impact one can get from the boulders no longer supported by the ice.

Well it's certainly true that ice can be heavy enough to cause loading problems: in ships rigging for example this quote from a Canadian Coast Guard page:

"Freezing spray: Ice which forms on a ship's hull and topside facilities as sea spray comes in contact with cold metal.

Super-structure icing: The formation of ice on a ship's hull or deck facilities, caused by freezing sea spray, precipitation, or fog.

Vessels operating in Canadian waters in late fall and winter are likely to experience some degree of topside icing on decks, bulwarks, rails, rigging, and spars. Icing can hinder shipboard activity and, in extreme cases, it can seriously impair vessel operations and stability. The accumulation of ice on a ship's superstructure can raise the centre of gravity, lower the speed and produce difficulty in manoeuvering. Icing can also cause various problems with cargo handling equipment, hatches, anchors, winches, and the windlass. Smaller vessels are most at risk, and several fishing vessels have been lost off the Canadian east coast because of spray icing.

.....Freezing spray can be experienced in almost all Canadian waters, although it is more frequent and more severe in coastal waters off eastern Canada. Ice accretion rates from freezing spray can exceed 2 cm/hr and ice build-up of over 25 cm is not uncommon. " I guess there could be impact forces as well on the deck, when ice thaws...

On land in buildings, you're apt to get big icicles where the roof is poorly insulated - it's a sure sign of heat loss and trouble with the energy design. The worst loading would be expected on the eaves, rather than impacts on deck, steps or patio structures exposed to thawing and falling ice, assuming these outside structures are already designed to bear normal heavy loads.

I don't know if The Deadliest Catch has done a show involving the icing up of a load of crab pots under adverse conditions, but I once worked with a crab fisherman whose boat capsized as a result of this. It turned him into a research subject for frostbite treatments. The book Working on the Edge, by Spike Walker (no relation), describes this life quite well.

Yeah, there's no doubt that freezing spray can capsize a boat. The conditions that cause it are usually directional, as in blowing a gale, so the ice buildup is not evenly distributed and instead weighs the boat down on one side. Any stack of gear as well as superstructure or rigging is subject to it, and contributes to adverse effects on balance and stability. Scary stuff.

Yes, they have. In addition to everything else they have to do these poor guys have to pound ice off the pots and rigging to stay upright.

One guy had to dump the top layer of pots just to keep from capsizing.

Water expands about 13% in volume as it freezes, contracts as it thaws and heats to about 4°C, and then expands gradually until boiling.