Calculation of the C3A Percentage in High Sulfur Clinker

The aim of this paper is to clarify the influence of the clinker SO3 on the amount of C3A. The calculation of the cement phases percentages is based on the research work, Calculation of the Compounds in Portland Cement, published by Bogue in 1929 .The usage of high sulphur fuels, industrial wastes, and tires changes completely the working condition of Bogue because the assumed phase compositions may change. The results prove that increasing the amount of SO3 in the low alkali clinker decreases the percentages of C3A due to the high incorporation of alumina in the clinker phases mainly C2S and C3S. The correlation is linear till the clinker SO3 reaches the 2%. Over that the influence of the clinker SO3 became undetectable. A new calculation method for the determination of the C3A in the high sulphur and low alkali clinker was proposed

doi:10.1155/2010/102146 Research Article Calculation of the C3A Percentage in High Sulfur Clinker

Copyright © 2010 Sayed Horkoss et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The aim of this paper is to clarify the influence of the clinker SO3 on the amount of C3A. The calculation of the cement phases percentages is based on the research work, Calculation of the Compounds in Portland Cement, published by Bogue in 1929.The usage of high sulphur fuels, industrial wastes, and tires changes completely the working condition of Bogue because the assumed phase compositions may change. The results prove that increasing the amount of SO3 in the low alkali clinker decreases the percentages of C3A due to the high incorporation of alumina in the clinker phases mainly C2S and C3S. The correlation is linear till the clinker SO3 reaches the 2%. Over that the influence of the clinker SO3 became undetectable. A new calculation method for the determination of the C3A in the high sulphur and low alkali clinker was proposed. 1

The effect of the source of cement SO 3 on the expansion of mortars

International audienceIn order to evaluate the risk of the source and quantity of cement SO3 on the expansion properties of mortars, this paper studied the influence of Gypsum, Bassanite and clinker sulfate on the cement paste expansion and the formation of delayed ettringite. The investigation covers the mortar cured at 20 °C and 80 °C and stored in water. In contradiction to many studies, the results showed that the cement produced with high sulfur clinker had lower expansion than that produced with classical gypsum or high soluble Bassanite. In addition to that, we have detected that the percentage of SO3, in the cement, could increase the risk of DEF if it surpasses the level of 3.5%. Also, the curing temperature at 80 °C affects the microstructure of concrete by generating cracks in the cement paste

Influence of clinker sulfate on cement paste external sulfate attack

WOS:000321425900005International audienceThis paper aims to clarify the influence of the clinker sulfate on external sulfate attack of cement paste. The investigation shows that the clinker sulfate does not have any direct influence on the resistance of cement to external sulfate attack. Indirectly this sulfate reduces the amount of tricalcium aluminate (C(3)A) and tricalcium silicate (C3S), generating an improvement in the level of cement resistance to external sulfate attack. The mortar expansions, after 1 year of storage in 5% sodium sulfate (Na2SO4) solution, verify the mineralogical results. Additionally the investigation indicates that the combination of the three techniques - X-ray diffraction analysis, scanning electron microscopy and graphical treatment of microanalysis by energy-dispersive X-ray spectroscopy - leads to a better understanding of the causes of paste deterioration by external sulfate attack