Early heat evolution of different sized portland cements incorporating ground granulated blast furnace slag


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, İnşaat Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2013

Öğrenci: CAN ÇETİN

Eş Danışman: SİNAN TURHAN ERDOĞAN, MUSTAFA TOKYAY

Özet:

Heat of hydration and rate of heat evolution are two important characteristics of portland cement hydration, significant for various concrete applications such as mass, hot-weather, and cold-weather concreting. The heat of hydration and rate of heat liberation of cement pastes, and concrete made with it, depend heavily on the chemical composition, fineness, and mineral admixture content of the cement used. This thesis investigates the influence of compound composition and GGBFS incorporation in different-sized portland cements on early heat of hydration and rate of heat liberation. Several portland cements are produced by intergrinding clinker, gypsum and GGBFS in different proportions. The cements are sieved into different particle size interval. Particle size distribution of each sample formed after sieving is measured with the laser diffraction method. Heat of hydration of samples is measured with an isothermal conduction calorimeter. Moreover, compound composition of each sample is calculated using the results of chemical analysis and quantitative determination of constituents. The result of each analysis is used to generate a correlation between fineness, GGBFS incorporation, chemical composition and heat of hydration. It is found in this study that early heat of hydration and rate of heat evolution decrease as the content of GGBFS is increased. Moreover, the heat peak that occurs due to renewed ettringite formation occurs earlier as the content of gypsum decreases, alkalis and the content of GGBFS increases. Finally, GGBFS content decreases and C2S content increases in the finer portions of the cements.