Rheological properties of freshly poured, steel fibrereinforced, self-compacting concrete

This paper discusses the methodology and findings of an investigation on the influence of steel fibres on rheological and mechanical properties of Steel Fibre Reinforced Self-Compacting Concrete (SFRSCC). The rheological properties of SFRSCC behave just like a Bingham body for which the rheological parameters “yield value g” and “plastic viscosity h” were determined using a new kind of BT2 rheometer for research on mortars and concrete mixes. SFRSCC’s mechanical parameter of compressive strength fc in a cube is discussed as well. In the present research, an experimental verification of the influence and significance of the following factors on the rheological properties of SFRSCC was carried out: fibre volume ratio, fibre factor, fibre length and fibre shape. Also, the findings obtained for mixes with three types of steel fibre shapes are presented. The concrete mixes were prepared in such a fashion that they provided the required workability and properties of concrete once it has hardened. Fibre length apparently has no significant influence on yield value g and plastic viscosity h of SFRSCC. Only in the case of hooked steel fibres, fibre length exerted a significant influence on plastic viscosity h. The rheological properties of SFRSCC from the aspect of workability appear more favourable for SCC’s than with other types of fibres.

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