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Founded in 1904 and headquartered in Farmington Hills, Michigan, USA, the American Concrete Institute is a leading authority and resource worldwide for the development, dissemination, and adoption of its consensus-based standards, technical resources, educational programs, and proven expertise for individuals and organizations involved in concrete design, construction, and materials, who share a commitment to pursuing the best use of concrete.
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Home > Tools > Frequently Asked Questions
Q. How does the temperature influence curing? A. The higher the temperature, the more rapidly the hydration and pozzolanic reactions proceed. Tests of specimens sealed against loss of moisture show higher early strengths but lower strengths at later ages as the temperature is increased above 5°C (40°F). At temperatures below 5°C (40°F), the rate of hydration is greatly retarded. At freezing temperatures, special admixtures are used for strength development. For temperatures between 5 and 15°C (40 and 60°F), satisfactory results can be obtained by prolonging the moist curing period. For job control specimens cured at 20°C (68°F), lower temperatures at the time of casting and for a few hours thereafter give higher strengths at one to three months. The rapid stiffening in the first few hours and the rapid rate of early strength development under the higher temperatures are detrimental to the later development of strength. References: SP-1(02); ACI 308R-16; ACI 209R-92; ACI 302.1R-15 Topics in Concrete: Concrete Fundamentals; Curing; Placing
Q. How does the temperature influence curing?
A. The higher the temperature, the more rapidly the hydration and pozzolanic reactions proceed. Tests of specimens sealed against loss of moisture show higher early strengths but lower strengths at later ages as the temperature is increased above 5°C (40°F). At temperatures below 5°C (40°F), the rate of hydration is greatly retarded. At freezing temperatures, special admixtures are used for strength development. For temperatures between 5 and 15°C (40 and 60°F), satisfactory results can be obtained by prolonging the moist curing period. For job control specimens cured at 20°C (68°F), lower temperatures at the time of casting and for a few hours thereafter give higher strengths at one to three months. The rapid stiffening in the first few hours and the rapid rate of early strength development under the higher temperatures are detrimental to the later development of strength.
References: SP-1(02); ACI 308R-16; ACI 209R-92; ACI 302.1R-15
Topics in Concrete: Concrete Fundamentals; Curing; Placing
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