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1) English breakfast.Now this must be the secret of Jack Sparrow, how he never fell into hangover trap. Curing is the process in which the concrete is protected from loss of moisture and kept within a reasonable temperature range. When smart, suitable, and practical curing is used, the amount of cement required to achieve a given strength and durability can be reduced by either omission or replacement with supplementary cementitious materials. Typical recommendations for curing of pavements allow the use of sheet curing, moist curing, or application of a film forming curing compound.
In contrast, concrete bridges require a higher standard of curing to achieve the low permeability required for protection of steel reinforcement.
Typical moist curing for bridge decks requires the application of adequate quality water saturated burlap or other approved absorptive material covered with minimum six mil plastic covering. In order to meet this expected service life, it must be able to withstand structural loading, fatigue, weathering, abrasion, and chemical attack. Since the cement is the most expensive and energy intensive portion of a concrete mixture, this leads to a reduction in the cost as well as the absolute carbon footprint of the concrete mixture.

Due to the large surface areas typical of concrete paving the application of curing compound to all exposed surfaces is the most common curing method.
Standard recommendations for curing bridge decks is moist curing for a minimum of seven days for concrete mixtures containing only portland cement and as long as 14 days when supplementary cementing materials are included in the concrete mixture. Curing is also a key player in mitigating cracks in the concrete, which severely impacts durability. Additionally, practical curing methods can enhance sustainability by reducing the need for resource intensive conditioning treatments, should the curing method be incompatible with the intended service environment. Moist curing and sheet curing of large surface areas may become cost prohibitive due to the large quantity of materials required to cover the full surface of concrete placed in any single day.
In most cases plastic will be specified to be white in color to reflect solar radiation, reducing the temperature rise beneath the plastic, while cold temperatures (less than 50 degrees Fahrenheit) may allow the use of black plastic to add heat to the system. The Link Between Concrete Sustainability and Curing Sustainability, according to the Bruntland Report and adopted by many experts, is development that meets the needs of the present without compromising the ability of future generations to meet their own needs. Cracks allow open access for harmful materials to bypass the low permeability concrete near the surface.

In addition moist curing and sheet curing require maintenance to assure the curing method is properly completed for the full time duration chosen for paving (typically seven days). Proper moist curing will also require uncovering and rewetting the absorptive material to assure that there is a constant supply of water available to satisfy the evaporation rate at the project site.
Moist coverings require rewetting and sheet goods are prone to being disturbed by wind, either of which would reduce the effectiveness of the curing method.
For more information, see Design and Control of Concrete Mixtures, 15th Edition, EB001. Both categories have basic requirements for the durability of the structures including strength, abrasion resistance, freezing and thawing and deicer resistance, and, in the case of bridges, low permeability for corrosion protection of the reinforcement of the structure.

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