Contributions
matching >Feys.D<
Follow the blue link(s) below for abstracts and full text pdfs 
.
Author index ►
Most cited recent articles ►
Articles for free download ►
Search conferences ►
Dimitri Feys, Ronny Verhoeven, Geert De Schutter
Extension of the Poiseuille formula for shear-thickening materials and application to Self-Compacting Concrete
Appl. Rheol. 18:6 (2008) 62705 (11 pages)
►
In practice, while placing concrete in a formwork by pumping, the pressure generated by the pump is not controlled. In order
to enhance the safety on the worksite, and in view of the current economic and ecologic arguments, it would be useful to dispose
of an equation able to predict pressure losses based on the rheological properties of the concrete and the pipe configuration.
This paper describes the derivation of an extended version of the Poiseuille formula, for shear-thickening materials
with a yields stress, described by the modified Bingham equation. This formula is applied to flow-tests with self-compacting
concrete. The results prove the applicability of this extended Poiseuille formula, showing that the flow is occurring in laminar
regime, with no significant wall slip.
► Cite this publication as follows:
Feys D, Verhoeven R, DeSchutter G: Extension of the Poiseuille formula for shear-thickening materials and application to Self-Compacting Concrete, Appl. Rheol. 18 (2008) 62705.
Dimitri Feys, Ronny Verhoeven, Geert De Schutter
Evaluation of time independent rheological models applicable to fresh Self-Compacting Concrete
Appl. Rheol. 17:5 (2007) 56244 (10 pages)
►
Self-Compacting Concrete is a new type of concrete which is more liquid compared to traditional concrete and which does
not need any form of external compaction. As a result this type of concrete is suitable for a new placing technique: pumping
SCC from the bottom in the formwork and letting it rise in the formwork due to the applied pressure. In order to understand
the phenomena occurring during pumping operations, the rheological properties of SCC must be investigated and controlled.
Tests have been performed with two different rheometers, which are described in this paper. For the Tattersall Mk-II rheometer,
a calibration procedure has been worked out to eliminate secondary flows in the rheometer.Test results indicate that SCC
is a thixotropic liquid, having a yield stress, showing shear thickening and having varying properties in time due to the occurring
chemical reactions. In this paper, the time dependent effects will not be described. When trying to apply a rheological
model to the obtained results, only the modified Bingham model seems appropriate. Applying the Bingham model results in
the generation of negative yield stresses while the Herschel-Bulkley model has a parameter with a variable dimension and
has a major mathematical restriction. The rheological properties of fresh SCC can be described with the modified Bingham
model. A suitable parameter to describe shear thickening is defined as the ratio of the second order term in the shear rate of
the modified Bingham model to the linear term (= c/μ).
► Cite this publication as follows:
Feys D, Verhoeven R, DeSchutter G: Evaluation of time independent rheological models applicable to fresh Self-Compacting Concrete, Appl. Rheol. 17 (2007) 56244.
© Applied Rheology 2024
