Rheology of Fibre Reinforced Fine-Grained High Performance Concrete for Thin-Walled Elements - Effect of Type and Content of Steel Fibres

Concretes for thin-walled shell structures have to provide both high strength and flowability. Both can be achieved by reinforcing high strength fine-grained concretes with high contents of steel fibres. However, steel fibres can have a significant effect on the flowability and, as a result, the yield stress and viscosity of the fresh concrete. The present investigations show the effect of increased fibre contents on the rheological parameters yield stress and viscosity of high strength fine-grained concrete. These parameters were determined by using a rheometer. The suitability of fine-grained concretes for filling thin-walled formwork while maintaining flowability was determined by the time-dependent flow distance in an L-box model formwork. It was shown that there is a critical fibre content beyond which both the yield stress and the viscosity increase strongly. This affects the form filling ability of the concrete containing fibres.      «

Concretes for thin-walled shell structures have to provide both high strength and flowability. Both can be achieved by reinforcing high strength fine-grained concretes with high contents of steel fibres. However, steel fibres can have a significant effect on the flowability and, as a result, the yield stress and viscosity of the fresh concrete. The present investigations show the effect of increased fibre contents on the rheological parameters yield stress and viscosity of high strength fine-gr...     »