Mass concrete is defined by the American Concrete Institute as: “any volume of concrete in which a combination of dimensions of the member being cast, the boundary conditions, the characteristics of the concrete mixture, and the ambient conditions can lead to undesirable thermal stresses, cracking, deleterious chemical reactions, or reduction in the long-term strength as a result of elevated concrete temperature due to heat from hydration.”
As interior temperature of mass concrete rises due to the process of cement hydration, the outer concrete may be cooling and contracting. If the temperature differs too much within the structure, the material can crack. The main factors influencing temperature variation in the mass concrete structure are: the size of the structure, the ambient temperature, the initial temperature of the concrete at time of placement and curing program, the cement type, and the cement contents in the mix.
As interior temperature of mass concrete rises due to the process of cement hydration, the outer concrete may be cooling and contracting. If the temperature differs too much within the structure, the material can crack. The main factors influencing temperature variation in the mass concrete structure are: the size of the structure, the ambient temperature, the initial temperature of the concrete at time of placement and curing program, the cement type, and the cement contents in the mix.
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