Optimization of selfcompacting concretes mixing design

Abstract

Using selfcompacting concretes brings benefits such as productivity increase, noise reduction and energy save, so its utilizations is highly recommended. Nevertheless the concretes design requires carefull study and proper proportion of materials.
It’s important the amount of variables that intervene in designing concrete, and selfcompacting in particular being the proportion of aggregate one of the most important fact in influencing the characteristics of these concretes.
Due to this importance this paper presents results in searching of optimization for an appropriate proportion between fine and coarse aggregates, allowing maximum benefits of these concretes.
It was settled a dosage pattern while maintaining constant the volume of aggregates. The variable is the relation fine aggregate/aggregate total, finding practically the optimum that facilitates the dosage of concrete.
In fresh and hardened state properties for each relation were measured: selfcompactibility, ability to step, filling capacity and resistance to segregation properties were studied in fresh state
In hardened state results of resistance to compression at 7 and 28 days of age are presented.
Results suggest that mixing optimization is possible from a correct choice of the relation between the content of fine aggregates and the total of aggregates.