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The addition of an accelerator speeds the setting time and thus cure time starts earlier. [1] This allows concrete to be placed in winter with reduced risk of frost damage. [2] Concrete is damaged if it does not reach a strength of 500 pounds per square inch (3.4 MPa) before freezing. [3]: 19
Therefore, when concreting at cold temperature cannot be avoided, it is essential to have a minimum curing time at a temperature sufficiently above the freezing point of the concrete pore water, so that the early strength of concrete is high enough to resist the inner tensile stress caused by water freezing. [5]
Accelerated curing is any method by which high early age strength is achieved in concrete. These techniques are especially useful in the prefabrication industry, wherein high early age strength enables the removal of the formwork within 24 hours, thereby reducing the cycle time, resulting in cost-saving benefits. [ 1 ]
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How fast does a 50-gallon rain barrel fill up? How fast a 50-gallon rain barrel fills up depends on the intensity and duration of rainfall and the size of the catchment area (such as the roof).
Likewise, time reduction reduces installation costs. Regular, membrane-backed concrete can cost around US$5 per square foot, although prices can vary based on the application. The one-step installation process of hydrophobic concrete brings the cost down to about US$3.20 per square foot.
In arid climates, rain barrels are often used to store water during the rainy season for use during dryer periods. Rainwater tanks may have a high (perceived) initial cost. However, many homes use small scale rain barrels to harvest minute quantities of water for landscaping/gardening applications rather than as a potable water surrogate.
E.g. A 10-year-old concrete slab can contain more moisture than a 28-day-old slab! Conversely, a self-drying concrete blend consumes all of its mix water with a water:cement ratio of up to 0.6, maintaining good workability while allowing flooring to be installed before it is completely dry.