Experimental Characterization of Age-Dependency of Shrinkage Coefficient of Hardening Concrete

다국어 초록 (Multilingual Abstract)

This study experimentally investigated the shrinkage coefficient of hardening concrete which describes free drying shrinkage per unit change in internal relative humidity. While existing studies suggested the age-independency of the coefficient, this study indicated that the coefficient had strong age-dependency. The coefficient was greater at early ages and diminished and converged to a constant as hardening of concrete progressed. The numerical analysis implied that age-dependency of the coefficient had a considerable effect on drying shrinkage stress development in concrete structures. The experimental method in this study quantitatively evaluated the drying shrinkage of hardening concrete in terms of internal relative humidity changes, which eventually allows realistic assessments of drying shrinkage stress development in the early-age concrete structures in the field.

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