Concrete Block Insulating Systems’ patent-pending TempGuard from Eskimold, a 4- x 8-in. EPS foam mold, replaces plastic concrete test cylinders and eliminates nearly all need for curing boxes. TempGuard’s insulating properties dramatically reduce and slow the detrimental effects variable jobsite temperatures have on concrete test cylinder curing, product developers note.
The mold performs in hot or cold conditions by moderating specimen temperature changes and ensuring the test material cures more like the in-place concrete. TempGuard nets what Eskimold engineers contend are “better and more realistic test results in both jobsite and factory environments, without any change from regular specimen handling or testing methods.”
— Eskimold Products, 800/214-3750, 414/559-6434; www.eskimold.net
Elapsed time vs. temperature drop
Testing specimen stability in cold weather conditions, Eskimold engineers placed fresh concrete, measured at 73.5°F, in plastic and TempGuard cylinders at 25° ambient outdoor temperature. Concrete in the plastic cylinder dipped to 32° in about five hours, about one-quarter the time the TempGuard specimen held above freezing.
Testing warm weather conditions and stable curing prospects, Eskimold engineers placed fresh concrete on a mildly warm day in TempGuard and standard cylinders. Based on test results provided by Con-Cure Concrete Maturing Solutions, the latter specimen exhibited a 30°F swing above and below the TempGuard specimen, leading to the potential crossover effect: Higher early temperatures yield higher early but lower long-term concrete strength.