Off course, the answers above are totally true but the degree and rate of hydration or heat rate development affects the risk of cracking and higher or lower strength. Besides, mass concrete is directly affected by hydration heat. If the ambient temperature is above (High pressure high temperature steam curing which is autoclaving) 100-150 degrees celcius at early curing ages, the CSH also may transforms to a crystal structure which leads to decrease in ultimate mechanical properties (long term) . The heat of hydration depends on the type and fineness of cement and the temperature is needed for the development of hydration but heat hydration contributes to the curing temperature, it may not lead to crytal CSH forms which does not have binding or strength gaining property but it definetly causes to evaporation of free water in capillar pores thus, increases drying shrinkage. Consequently, I would like to say we jave to control the hydration rate and the amount of hydration heat to optimize the fresh and hardened concrete properties.
PS: I could not write the symbols of crystal CSH because I do not know kow to write symbols in this message section.
For sure higher heat of hydration causes higher temperature in concrete structure and that increases the risk of cracking.
Also the higher temperature of concrete accelerates strength development. Because due to the Arhenius law the maturity of concrete depends on temperature history, and based on maturity method one can estimate concrete strength.
But I have no idea if there is a correlation between the heat of hydration and maximum value of concrete strength and I'll gladly read the others' answers.
Of course when heat temperature is going up the igneous shrinkage will increase so crack will happen, and actually the temperature is one of the important reason for reaching concrete to high strength in short time, thats why the autoclaving is using in these days as curing method
Off course, the answers above are totally true but the degree and rate of hydration or heat rate development affects the risk of cracking and higher or lower strength. Besides, mass concrete is directly affected by hydration heat. If the ambient temperature is above (High pressure high temperature steam curing which is autoclaving) 100-150 degrees celcius at early curing ages, the CSH also may transforms to a crystal structure which leads to decrease in ultimate mechanical properties (long term) . The heat of hydration depends on the type and fineness of cement and the temperature is needed for the development of hydration but heat hydration contributes to the curing temperature, it may not lead to crytal CSH forms which does not have binding or strength gaining property but it definetly causes to evaporation of free water in capillar pores thus, increases drying shrinkage. Consequently, I would like to say we jave to control the hydration rate and the amount of hydration heat to optimize the fresh and hardened concrete properties.
PS: I could not write the symbols of crystal CSH because I do not know kow to write symbols in this message section.
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