Simultaneous determination of the sorption isotherm and water diffusivity of cement-based materials

Author(s): S. Tada
Paper category: Workshop
Book title: International RILEM Workshop on Performance Based Evaluation and Indicators for Concrete Durability
Editor(s): V. Baroghel-Bouny, C. Andrade, R. Torrent, K. Scrivener
ISBN: 978-2-912143-95-2
Pages: 83 - 87
Total Pages: 5
Language: English

Abstract: 
Throughout their service lives, cement based materials are substantially influenced by moisture transport and water phase changes. Numerical solution of moisture balance equations can provide time-dependent moisture content profiles, but coefficients in the equations have to be determined in experiment with considerable time and care. A rapid method to determine both the sorption isotherm and water diffusivity at the same time is presented in this paper. Humidity boundary conditions were applied to the specimens, and the resulting water adsorption was continuously recorded in a sufficiently short period. The diffusion equation was analytically solved and was curve-fitted to the adsorption rate, resulting in the rapid estimation of both the equilibrium water content and the water diffusivity. Results of the sorption isotherm and water diffusivity showed good agreement with those measured by the conventional methods.

Online publication: 2007
Publication Type: full_text
Public price (Euros): 0.00