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Load due to ice expansion in open tank 1

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bootlegend

Structural
Joined
Mar 1, 2005
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For those of you that design tanks, is there any literature on expansion loads due to water freezing in a slurry tank? I am looking at a roughly 40' length by 14' width by 12' depth open-top concrete slurry tank. My initial thought was that the expansion would move upward since there is no resistance, but now I'm picturing the possibility of only a couple feet of water in the tank. The top freezes first and adheres to the edges so that the water beneath is confined as it freezes.

 
Bootlegend:
I think that your thinking in your last sentence is about right. The ice will bond/freeze to the concrete wall, just as it does to foundation walls and piers. The old, milk in a glass bottle example is different because the bond to the glass was very low and lubed by butter fat, and that doesn’t freeze strong either. The forces of expansion are a function of the ice expansion coefficient, times the extent of the ice sheet, vs. the strength of the ice and the strength of the tank walls. The slurry might produce a real weak ice sheet, which crushes under compression before overloading the tank walls. One solution to this problem, during the freezing season, is to put something in the tank which compresses easily and changes volume in doing so, to allow the ice expansion. Descriptive licence here to make my point: 12" dia. balloons, one 40' long and the other 14' long, along the two walls, weighted down so only a couple inches was above the surface. This would allow 6 or 8" of ice formation still acting against the side of the balloons. Maybe these could be 8" wide x 12-14" deep foam rubber logs, again weighted down.
 
This reminds me of a swimming pool at a camp I attended when I was young. In the winter, the pool was closed and logs (maybe power poles?) were floating in the pool. When the water froze, it pushed the logs up rather than break the pool. I don't remember any other details.
 
Put a slight draft on the walls.
 
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