ESTIMATION METHOD OF COMPRESSIVE STRENGTH OF BLENDED CEMENT PASTE WITH DIFFERENT BINDER COMPOSITION, WATER TO BINDER RATIO AND CURING TEMPERATURE BY CONDUCTION CALORIMETER

• Published in: Cement Science and Concrete Technology Vol. 71; no. 1; pp. 232 - 239
• Main Authors: YODA, Yuya, KIYOMURA, Syunsuke, KURODA, Yasuhiro, SAKAI, Etsuo
• Format: Journal Article
• Language: Japanese
• Published: Japan Cement Association 30.03.2018
• Subjects: Blast furnace slag; Blended cement; Compressive strength; Fly ash; Gel space ratio; Heat of hydration
• ISSN: 0916-3182; 2187-3313
• DOI: 10.14250/cement.71.232

Strength is produced by the hydration reactions of cement, so much research has been carried out into the effect of hydration reactions on strength properties. However, some cases have been confirmed where gel space ratio, the theory that connects hydration reactions and strength properties, does not apply when admixtures are used. In this research, the objective was to construct a method of estimating the strength from hydration reactions, that is not dependent on admixture percentage and type. The parameters were binder composition, water to binder ratio, and curing temperature. The effect of hydration reactions on the strength properties of blended cements in which a prescribed percentage of ordinary Portland cement was replaced with various admixtures was investigated. Hydration reactions were analyzed using the cumulative heat of hydration obtained using a conduction calorimeter. The cumulative heat of hydration was allocated into that originating from the Portland cement and that originating from the admixtures and the relationships between the cumulative heat of hydration and the strength properties were compared and analyzed. The results showed that the relationship between heat of reaction originating from the admixtures and the strength properties was different from that for ordinary Portland cement, and this difference was defined quantitatively as a material coefficient. Also, gel space ratio has been extended so that by using the material constants it enables the strength properties to be estimated from the cumulative heat of hydration for different binder composition, water to binder ratio, and curing temperature.