On the physico-chemical evolution of low-pH and CEM I cement pastes interacting with Callovo-Oxfordian pore water under its in situ CO2 partial pressure

被引：55

作者：

Dauzeres, A. ^{[1
,2
,7
]}

Le Bescop, P. ^{[1
]}

Cau-Dit-Coumes, C. ^{[3
]}

Brunet, F. ^{[4
]}

Bourbon, X. ^{[5
]}

Timonen, J. ^{[6
]}

Voutilainen, M. ^{[6
]}

Chomat, L. ^{[1
]}

Sardini, P. ^{[2
]}

机构：

[1] CEA, DEN, DPC, SCCME,Lab Etude Comportement Betons Argiles, F-92262 Fontenay Aux Roses, France

[2] Univ Poitiers, UMR CNRS, Lab HYDRASA, F-6269 Poitiers, France

[3] CEA, DEN, DTCD, SPDE,Lab Etude Enrobage Dechets, F-30207 Bagnols Sur Ceze, France

[4] CEA, IRAMIS, S1S2M, Lab Struct & Dynam Resomance Magnet, F-91191 Gif Sur Yvette, France

[5] Andra Sci Div, F-92298 Chatenay Malabry, France

[6] Univ Jyvaskyla, Dept Phys, FIN-40351 Jyvaskyla, Finland

[7] IRSN, F-92262 Fontenay Aux Roses, France

来源：

CEMENT AND CONCRETE RESEARCH | 2014年 / 58卷

关键词：

Microstructure; Carbonation; Cement paste; Durability; Degradation; X-RAY MICROTOMOGRAPHY; AGGRESSIVE ENVIRONMENTS; WASTE-DISPOSAL; LOW-ALKALINITY; LOW-HEAT; CONCRETE; MICROSTRUCTURE; REPOSITORIES; DEGRADATION; DURABILITY;

D O I：

10.1016/j.cemconres.2014.01.010

中图分类号：

TU [建筑科学];

学科分类号：

0813 ;

摘要：

Within the framework of geological repositories for radioactive waste, structural concretes must be adapted to the underground chemical conditions. CEM I cement-based materials are characterised by high pH that may produce an alkaline plume in the near-field of the repository. In order to avoid this problem, low-pH cements have been designed. This study compares the physico-chemical behaviour of a low-pH material with a CEM I cement paste, both being subjected to leaching by an aqueous solution. An original experimental setup was designed to reproduce the underground conditions using a specific CO2 regulation device. Under these conditions, the low-pH material was strongly degraded, which results in coarser porosity, whereas thickness degradation of the CEM I cement paste is limited by the precipitation of a magnesium-calcite crust over the surface, which reduces the exchange of soluble species. This paper also presents a new approach for microstructure characterisation based on high-resolution X-ray microtomography. (C) 2014 Elsevier Ltd. All rights reserved.

引用

页码：76 / 88

页数：13