Admixtures in Concrete Construction Zusatzmittel im Betonbau

Abstract

Concrete is traditionally composed of water, cement and aggregates (sand, gravel). Through the variation of type and amount of these three components, many different types of concrete can be produced. By the addition of chemical admixtures, the field of concrete application has been extended during the last decades. In this paper, admixtures like superplasticizers, air-entraining agents, accelerators, retarders are beyond the scope. In the field of concrete technology, it is the aim to predict more precisely how admixtures work. New knowledge in the field of superplasticizers is presented. The influence of electrostatic and steric repulsive force on the dispersion of cement particels is shown. Beside the technical aspects, environmental concerns arose due to the increasing use of admixtures. Many questions may be answered today and show the environmental benefit due to the use of admixtures, but some are still open.