Caractérisation des propriétés thermiques des liants hydrauliques au jeune âge: ciment et pouzzolane

Abstract

Cementitious matrices made up with mineral addition were the subject of many studies. However, no rule has yet been found to quantify the effects of such additions, against the performance of mortars, as the mixing of different materials is not a simple operation, because of incompatibilities that may exist between individual components. In addition, the mixture of materials compatible does not always lead to the same results; interactions (or interactivity) are possible exist between different types of materials. These interactions can occur through synergies or antagonisms among the settlers, and are difficult to detect. Thus, few studies have been conducted to highlight the potential interactions between different components of the cementitious mixtures. Researchers recognize the need for complex and powerful tools for studies in this area. The objective of this study was to examine the use of natural pozzolan of Beni-Saf and synthetic pozzolana produced from the mud of the dam as fraction Fergoug substitution for Portland cement in the mortar, and for assessing their effects on mechanical strength at early age, and that to recover these wastes in cement industry. The main results showed that the tensile strength in bending of mortars prepared with different rates of substitution of pozzolan or mud decreases with increasing the percentage of pozzolan addition whatsoever or vase, and this for all ages. The effect of pozzolan results in consumption of lime, while hydration is a reaction resulting in production of lime. The ability of pozzolanic materials to reduce heat of hydration is largely (thanks to that property setting of lime) used in the constructions in large mass, or the risk of cracking occurs.