Étude de l’influence des schistes calcinés sur la Réaction Alcali-Silice pour une meilleure valorisation en bétons de granulats réactifs

Abstract : The use of the so-called “potentially reactive” (PR) aggregates, with respect to Alkali-Silica Reaction (ASR), leads to concrete degradations. In order to avoid the expansion of concrete made with them, some mineral additions such as burnt oil shales (SC) can be used as substituents to the clinker. The present work has a two aims, first to better understand the role of the SC against ASR and then the behavior of the siliceous limestone PR of Brunnen towards ASR. Among the aggregates used, the Brunnen was characterized. The presence of crypto to micro-SiO2, consisting of monocrystalline quartz, seems to be very reactive by its small size and would engender the expansion of concretes based on this aggregate. Despite a mineralogical and textural complexity, a micro-SiO2 was highlighted. The action of SC towards ASR was then studied by a model reactor and finally in concretes. Results show a beneficial effect of SC in the model reactor, in spite of non optimal conditions to show the pozzolanic reaction. As far as that goes, SC allowed the decrease of concrete expansions under the threshold limit for a 17 %wt of SC for flint and 30 %wt of SC or with CEM II/B-M (S,T) 42,5 R (Robusto 4R-S) for siliceous limestones. SC could have a dual effect of inhibiting ASR by fixing alkalis on products of the pozzolanic reaction and also neutralizing alkalis on its micro-SiO2.
Complete list of metadatas

https://hal.archives-ouvertes.fr/tel-01682506
Contributor : Alexandra Bourdot <>
Submitted on : Friday, January 12, 2018 - 12:07:50 PM
Last modification on : Tuesday, July 16, 2019 - 10:15:13 PM

File

50376-2013-Bourdot.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : tel-01682506, version 1

Citation

Alexandra Bourdot. Étude de l’influence des schistes calcinés sur la Réaction Alcali-Silice pour une meilleure valorisation en bétons de granulats réactifs. Génie civil. Université de Lille 1 - Sciences et Technologies; Mines Douai, 2013. Français. ⟨tel-01682506⟩

Share

Metrics

Record views

201

Files downloads

77