[TowerTalk] exploding foundations
DB1
DB1 at Dccnet.com
Fri Sep 14 14:43:30 EDT 2007
All this talk of concrete exploding due to the moisture flashing to steam is "in my opinion" absolute crap. The only way steam can occur is if the water in the concrete is subject to atmospheric pressure otherwise regardless (almost) of temperature it stays in the liquid state.(Although water will boil at room temperature if you subject it to a vacuum. -14.7 psi.)
IE: Water in a car radiator with the cap on. Water boils at 212 F under atmospheric pressure (14.7psi).....for every pound of pressure you put on that water in an enclosed space, it raises the boiling point by 3 degrees F. so with a 15 lb radiator cap lets say, the boiling point of the water would be 257 F. When you release that cap the superheated liquid water flashes to steam at atmospheric pressure with 970 BTU's/Cu Ft of energy (970 BTUs is the amount of energy that is required to change 1 cu ft of water at 212F to Steam at 212F
As water in concrete "is" in an enclosed ( and for all intensive purposes air tight )space and is under tremendous pressure (*a big radiator cap if you will) , it cannot in all likelihood flash to steam.
This is however a great discussion (grin)
Derek VE7RE
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