Skip to Main content Skip to Navigation
Theses

Compatibilités et incompatibilités liants cimentaires/superplastifiants

Abstract : Currently required concrete strength imposes a lower water/cement ratio and use of superplasticizer to make easier the fresh material implementation. Polycarboxylate type products are very effective in the short term but can lead to a fast loss of workability in case of binder/superplasticizer incompatibility. The object of this work is the identification of cementitous phases involved in these rheological variations. Initially, flow of various superplasticized pastes is evaluated by a rheometer fitted with a ball measuring system. Compatible combinations flow like a Bingham's fluid. An incompatibility results in an increase of yield stress and plastic viscosity or rheological properties evolution into Herschel-Bulkley's fluid. Then, cement/superplasticizer combinations are characterized by rheological tests. Stiffening assessment of pastes and chemical characterisation of hydrated cements show that consistency is associated with amount and microstructure of formed ettringite. These parameters depend on initially present aluminate phase and calcium sulphates. Finally, study of synthetic cementitous systems states that calcium sulphates solubility, in presence of superplasticizer, is increased probably because Ca2+ ions complexation by polycarboxylates. As for the orthorhombic variety of aluminate phase, more reactive than cubic variety, it leads to a large amount of needle-shaped ettringite.
Document type :
Theses
Complete list of metadatas

Cited literature [75 references]  Display  Hide  Download

https://hal.univ-lorraine.fr/tel-01748559
Contributor : Thèses Ul <>
Submitted on : Thursday, March 29, 2018 - 11:38:16 AM
Last modification on : Thursday, February 25, 2021 - 11:04:56 AM
Long-term archiving on: : Friday, September 14, 2018 - 7:54:57 AM

File

SCD_T_2010_0052_NICOLAS.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : tel-01748559, version 1

Citation

Edwige Nicolas. Compatibilités et incompatibilités liants cimentaires/superplastifiants. Autre. Université Henri Poincaré - Nancy 1, 2010. Français. ⟨NNT : 2010NAN10052⟩. ⟨tel-01748559⟩

Share

Metrics

Record views

186

Files downloads

196