THE USE OF VISCOSITY ENHANCING ADMIXTURES TO IMPROVE THE HOMOGENEITY OF FIBRE DISTRIBUTION IN STEEL FIBRE REINFORCED CONCRETES

ABSTRACT This work presents the early results of a research program aimed at evaluating the influence of viscosity enhancing admixtures (VEA) on the fibre distribution in Steel Fibre Reinforced Concrete (SFRC) elements. First of all their influence has been investigated with reference to fibre distribution along casting direction in cylinder specimens. As a further step of the investigation small-scale prototypes have been cast with the same mixes previously tested and the distribution of fibres, as influenced by the mix-design of concrete, has been evaluated along the thickness, the cross-section and the longitudinal axis of the prototypes. Results are really promising in sight of structural applications. In this framework some full-scale prototypes have been cast with the “optimum” mix, as came out from previous experiments, and the repeatibility of results previously obtained has been checked with reference to them.

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