Prediction of Changes in Physical Properties due to Leaching of Hydration Products from Concrete

It is well known that degradation of properties such as increase in porosity of the surface layer and reduction in strength occur because of material transfer due to dissolution and diffusion of hydration products when concrete comes in contact with water. However, methods for quantitatively evaluating the changes in properties have not yet been established. The authors studied the applicability of immersion tests of cement paste using cation-exchange resin and studied actual concrete structures of ages ranging from 34 to 104 years. The authors also constructed a model of degradation for physical properties such as porosity and strength due to leaching, based on the results of these studies.

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