Dimensional Analysis of Ionic Transport Problems in Hydrated Cement Systems - Part 1: Theoretical Considerations

Published

December 1, 2000

Author(s)

R Barbarulo, J Marchand, Kenneth A. Snyder, S Prene

Abstract

The validity of the local equilibrium assumption in hydrated cement systems, that a particular chemical reaction is instantaneous with respect to transport, is examined using a dimensional analysis of electrochemical transport in cementitious materials. The transport equation parameters are scaled, resulting in a dimensionless equation. The dimensionless coefficient for each reaction/transport term determines its relative contribution to the overall process. The diffusion of ions in a reacting porous medium can be fully described on the basis of six independent dimensionless numbers. The analysis demonstrates that the kinetics of the reaction determines the appropriate time constant for the analysis. The formalism is applied to the dissolution of calcium hydroxide under an electrochemicalpotential gradient. The results are in agreement with previous observations and demonstrate quantitatively the local equilibrium hypothesis is valid in most practical cases where ions are transported by diffusion through a saturatedmaterial.

Citation

Cement and Concrete Research

Volume

30

Issue

No. 12

Pub Type

Journals

Download Paper

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Keywords

building technology, concrete, dimensional analysis, ionic transport, leaching, reaction

Citation

Barbarulo, R. , Marchand, J. , Snyder, K. and Prene, S. (2000), Dimensional Analysis of Ionic Transport Problems in Hydrated Cement Systems - Part 1: Theoretical Considerations, Cement and Concrete Research, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=860246 (Accessed April 19, 2024)