Influence of segregation on the performance of self-compacting concrete in the fresh and hardened states

The granular mixture represents one of most important parameters in the formulation of self-compacting concretes in order to achieve a representative granular distribution. A good resistance to segregation results in a regular distribution of the different sizes of the aggregates in all parts of the element, with the same granule density. The granular mixture must be homogeneous and representative, and has to be able to flow in the absence of dynamic and static segregation.The main objective of the present research is to study the influence of segregation on the performance of Self-compacting concrete in the fresh and hardened state, by determining the static segregation index according to the percentage of aggregates of class G 8/15 and that of aggregates of class G 3/8 in order to obtain a homogeneous granular mixture, whatever the volume of self-compacting concrete to be prepared. It is well acknowledged that the threshold of the discontinuation of granular mixing represents a new element with respect to segregation in concrete. The obtained results showed that the percentage of large aggregates has a significant influence on the segregation index and the performance of self-compacting concrete (SCC) at 28 days.