Determination of the efficiency coefficient of slag under various mixing and curing conditions

Currently the prediction of the strength of blended cement constitutes a major preoccupation leading the promoters of such constructions to be more and more interested in predicting the timing of removal of the framework or the prestressing at suitable ages. The prediction of the strength of the slag concrete, using simple models of prediction such as Feret's model, with the introduction of the concept of the equivalent binder, was studied and this led to the definition of an efficiency coefficient of the slag which defines the latter according to the cement. This efficiency coefficient, once deduced, characterised the slag from the El-Hadjar steel factory (Algeria) well and made it possible to predict the strength of a slag concrete of a given age and replacement level from the data of a reference concrete made without slag. This coefficient is defined on the basis of the age, the replacement level, the specific surface area of the slag and the curing temperature.