Abstract
This paper explores the hydro/mechanical behaviour of unsaturated engineered buffer. This is achieved via the assessment of a conceptual model for micromacro moisture flow. In particular the re-saturation behaviour of a large scale insitu experiment performed by Atomic Energy of Canada Limited, (AECL), is examined. Numerical simulations of the test are presented and the conceptual model investigated.
The experiment, known as the isothermal test, examines water inflow, from the surrounding rock, into highly compacted, unsaturated buffer material. Numerical simulations of the experiment are performed using an approach developed to model the thermo/hydraulic/mechanical behaviour of the system. The simulation of the experiment, using a “conventional” approach to describe the hydraulic conductivity of the buffer material, revealed that neither the duration nor the pattern of moisture influx could be modelled accurately. Further study suggested incorporation of a conceptual model for micro/macro moisture flow via the conductivity relationship may explain the experimentally observed behaviour. This approach yielded significant results with both the pattern and the rate of water uptake being simulated with a much greater accuracy.
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© 2005 Springer-Verlag Berlin Heidelberg
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Thomas, H.R., Cleall, P.J., Chandler, N., Dixon, D., Mitchell, H.P. (2005). Hydro-mechanical behaviour of unsaturated buffer. In: Schanz, T. (eds) Unsaturated Soils: Numerical and Theoretical Approaches. Springer Proceedings in Physics, vol 94. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-26737-9_23
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DOI: https://doi.org/10.1007/3-540-26737-9_23
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-21122-8
Online ISBN: 978-3-540-26737-9
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