A comparative assessment of selected Indian and South African cement clinkers

摘要

Knowledge of the thermal response of cement is important in the design and construction of high early strength concrete mixtures as well as mass concrete structures. This is because such structures present a high potential for cracking as a result of stresses induced by temperature gradients within the concrete. Heat is generated from the cement hydration reactions and both the quantity of heat as well as the rate at which this heat is evolved depends on the mineralogical and morphological characteristics of the cement clinker. This paper presents an assessment of the heat evolution of cement clinkers obtained from three cement production plants in South India. Cements were prepared in the laboratory by grinding the clinkers with gypsum from a single source and testing in an adiabatic calorimeter to determine the heat evolution characteristics of each of the clinker samples. X-ray fluorescence (XRF) analysis and optical microscopy were used to determine the chemical composition and to characterise the crystal size, morphology, and distribution of clinker phases. To provide an external basis for comparison, the results obtained from the Indian clinkers are compared with those of cement clinkers drawn from two production plants in South Africa.