Numerical Analysis of Unsaturated Seepage Flow in Two-Dimensional Fracture Networks
Publication: International Journal of Geomechanics
Volume 17, Issue 5
Abstract
Fracture-dominated flow in fractured rocks is of interest in many areas of scientific and technical research. In contrast to the continuum approach, this study employed a discrete fracture model method to analyze water movement in unsaturated fractured rocks, in which the flow behavior for single fractures is governed by Darcy’s law and the Richards equation, and the partial differential equations defined on the whole fracture network domain were formulated. A systematic finite-element algorithm was developed along with a corresponding numerical procedure. The results for the porous medium indicate that the proposed method is valid. Good agreement was found between the numerical predictions and experimental observations, and thus the equivalent discrete fracture network model may be used in place of the continuum model. The infiltration seepage analysis in a fractured rock slope demonstrated that the distribution of fracture-dominated flow was heterogeneous and that the movement of variably saturated seepage flow was substantially influenced by the orientation of fractures.
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Acknowledgments
The authors thank the associate editor and three anonymous reviewers for constructive comments. The work reported in this paper has received financial support from the National Natural Science Foundation of China (Grants 51079110, 51074115, 51409318, and 51509022), the National Basic Research Program of China (973 Program 2011CB013506), and the Natural Science Foundation of Hubei Province (Grant 2015CFA142).
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Published In
International Journal of Geomechanics
Volume 17 • Issue 5 • May 2017
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Oct 16, 2015
Accepted: Sep 7, 2016
Published online: Oct 5, 2016
Discussion open until: Mar 5, 2017
Published in print: May 1, 2017
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