Cement paste plastic shrinkage

At early age of cement paste reaction with water the plastic shrinkage occurs, which consists in evaporation of water from the surface layers of concrete [108]. The volume of fresh concrete is thus reduced. This process is not related to the properties of cement itself however it can also result in the formation of cracks. This situation is the consequence of substantial humidity gradient in concrete. The plastic shrinkage, equal 2.5 mm/m, observed in the 7 cm thick surface layer of concrete, was two times higher than the shrinkage in the core of element [108]. 

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