1. Leaching of reinforced concrete vaults subjected to variable water content due to capillary suction created by the seasonal temperature changes

Title: 1. Leaching of reinforced concrete vaults subjected to variable water content due to capillary suction created by the seasonal temperature changes
Author(s): P. Zuloaga, C. Andrade, M. Castellote
Paper category : conference
Book title: NUCPERF 2009 - Long Term Performance of Cementitious Barriers and Reinforced Concrete in Nuclear Power Plants and Waste Management
Editor(s): V. L'Hostis, R. Gens, C. Gallé
Print-ISBN: 978-2-35158-072-1
e-ISBN: 978-2-35158-087-5
Publisher: RILEM Publications SARL
Publication year: 2009
Pages: 3 - 11
Total Pages: 9
Nb references: 6
Language: English

Abstract: The variations of water content in concrete barriers of near surface disposal vaults, due to seasonal temperature changes, and the consequent differences of suction head induce a water flow; thus, advection and dispersion were considered as potential migration mechanisms.
Calcium leaching had been previously analysed through diffusion models. Focused on this aspect, this paper reports the progress of the experimental work and analytical studies developed for ENRESA by CSIC-IETCC, CSIC-IJA, UPC and CIEMAT on the behaviour of concrete barriers under such conditions. These works can be grouped in three axes: enhanced characterisation of thermo-hydraulic properties of concrete, reactive transport modelling and experimental work, among which the tasks related to calcium leaching are reported.

The thermo-hydraulic model previously presented appeared sensible to hydraulic
conductivity and retention curve parameters about which there was some lack of experimental
data.

Leaching of Calcium was studied in static and dynamic conditions, together with the analysis of leached concrete specimens. A reactive transport model, coupled with the thermohydraulic model was developed for the disposal conditions. Its aim is the representation of the migration of relevant elements and the assessment of the altered thickness. The output is compared to the experimental results.

Online publication: 2009-11-16
Publication type : full_text
Public price (Euros): 0.00