Obtaining a self-compacting concrete with finely ground coal slag

Abstract

This article presents the characteristics of fresh and hardened state of concrete mixtures modified with the addition of 10, 20, 30 and 50 % of finely ground coal slag as a partial replacement of cement. In order to verify their self-compactability, it was evaluated the performance of the optimal values for properties such as: the passing ability, filling ability and slump. In its fresh state, the concrete added with coal slag presented a very good workability and high level of cohesiveness among its components, with optimum qualities for formwork without vibration and without segregation. This achieved behaviour of the mixtures is characteristic of self-compacting concretes. On the other hand, the synergy of the addition of fine slag coal caused increases in the compressive strength of the concretes added with 10, 20 and 30 % w/w coal slag in orders of 18, 20, and 21%, respectively.