CRACK REDUCING METHOD OF MASS CONCRETE FOR MAT FOUNDATION CONSIDERING THE COMBINED ADDITION OF FLY ASH AND CHEMICAL ADMIXTURE

摘要

A method of reducing crack of foundation mass concrete according to the configuration combination of fly ash and chemical admixture is provided to completely control the hydration heat crack according to the pouring of the mixing concrete with the fly ash and the common portland cement. A method of reducing crack of foundation mass concrete according to the configuration combination of fly ash and chemical admixture divides upper and lower layers by equally dividing the section height of the mass concrete, pours the common portland cement at the upper layer, mixes a first admixture comprising a delaying AE water reducing agent or a delaying high AE water reducing agent of 0.01~1.5 weight% for the weight of the common portland cement, pours the mixing concrete with the fly ash and the common portland cement of 5~40 weight% for the weight of the common portland cement at the lower layer, and reduces the hydration heating value difference of the upper and lower layers by the combination of the admixture by mixing a second admixture comprising the both water reducing agents of 0.01~1.5 weight% for the weight of the mixing cement.