Evaluation of self-compacting concrete compositions based on particle size distribution and aggregates grading parameters

ABSTRACT

The self-compacting concrete (SCC) has been produced by different dosage methods. Some are based on the determination of paste and granular skeleton to achieve self-compactability. The search for aggregate packing with low voids content, which leads to a reduction in the paste volume, has been ideal. However, this model may not be the best for SCC. Particle systems with reduced voids and paste content can compromisse SCC self-compactability. On the other hand, compositions of aggregates with equal dosages between coarse and fine particles have been successfully proposed. In this context, the article aims to analyze aggregate compositions with dosages of similarly of coarse and fine aggregate, evaluating their continuous and discontinuous particle size distributions, in addition to determining graduation parameters, which can influence and contribute to the achievement of SCC self-compactability. The self-compacting properties were verified by the slump flow, visual stability index (VSI), V-funnel and L-box tests. The properties determined in the hardened state were: compressive strength, static elasticity module, water absorption by immersion, voids content and specific mass. For this, it were used especimes cylinders (10 cm x 20 cm). The results of this article showed that the graduation parameters of aggregates, obtained for each proportion and particle size distribution of the studied aggregate compositions the effect of the presence of fine particle diameters in relation to large particles, which can be clearly seen. the contribution of these parameters in the continuous and discontinuous distributions more closed for self-compacting concrete in compliance with the properties in the fresh and hardened state.

Keywords
Aggregates composition; Grading curves; Self-compacting concrete; Grading parameters