0000000000190815
AUTHOR
Laure Chomat
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
International audience; Abstract 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 materi…
Study of the hydration of cement with high slag content
International audience; The physico-chemical properties of cementitious materials, such as transport properties or porosity are established during the hydration process. The latter which involves dissolution and precipitation reactions, is characterized by the mineralogical and structural changes associated to water state (evolution from evaporable water to chemically bound water and physically absorbed water) and chemical shrinkage. These physico-chemical properties are modified by the addition of supplementary cementitious materials like slag. Powers' model, based on the water state repartition, was initially developed to describe the hydration of Portland cement. This work aims to apply …