50. A study on the dispersion/flocculation state and friction of cement particles in mortar based on the rules of deformability and amount of water bled by centrifugal force

Title: 50. A study on the dispersion/flocculation state and friction of cement particles in mortar based on the rules of deformability and amount of water bled by centrifugal force
Author(s): H. Nagamine, T. Kishi
Paper category : conference
Book title: 5th International RILEM Symposium on Self-Compacting Concrete
Editor(s): G. De Schutter and V. Boel
Print-ISBN: 978-2-35158-047-9
e-ISBN: 978-2-35158-088-2
Publisher: RILEM Publications SARL
Publication year: 2007
Pages: 341 - 346
Total Pages: 6
Language: English

Abstract: The authors determined the amount of water in mortar bled by centrifugal force to defined the percentage of this amount to powder volume as "WcsP". We found that it is an index of the space between two particles or an index of the dispersion / coagulation states of the particles derived from the relationship between "WcsP" and the deformability of mortar "µm". This study clarified the follows: (1)A focus exists among the linear relationships between "WcsP" and "µm" of mortars having various dosages of superplasticizers. (2) It indicates that in mortar on this focus, the water acting upon the fluidity is zero and the difference in "WcsP" from the focal point can be regarded as a new index "WP" of free water for fluidity.
By using the index "WfP" that also indicates the space between two particles, the categories of coagulation states of the particles are clearly classified based on the relationships between "WfP" and deformability of mortar and between "WfP". This study clarified the follows: (1) The coagulation states are loosened as the dosage of superplasticizer(SP) increases. (2) The coagulated body have two types of friction; one is "friction between the surfaces of the bodies", which influences on the deformability of mortar, and the other is "friction inside of the body", which influences on the viscosity of mortar.

Online publication: 2009-06-16
Publication type : full_text
Public price (Euros): 0.00