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http://dx.doi.org/10.7474/TUS.2011.21.2.117

The DFN-DEM Approach Applied to Investigate the Effects of Stress on Mechanical and Hydraulic Rock Mass Properties at Forsmark, Sweden  

Min, K.B. (서울대학교 에너지자원공학과)
Stephansson, O. (독일 지구과학 연구소)
Publication Information
Tunnel and Underground Space / v.21, no.2, 2011 , pp. 117-127 More about this Journal
Abstract
The purpose of this study is to demonstrate the effect of in-situ rock stresses on the deformability and permeability of fractured rocks. Geological data were taken from the site investigation at Forsmark, Sweden, conducted by Swedish Nuclear Fuel and Waste Man-agement Company (SKB). A set of numerical experiments was conducted to determine the equivalent mechanical properties (essentially, elastic moduli and Poisson's ratio) and permeability, using a Discrete Fracture Network-Discrete Element Method (DFN-DEM) approach. The results show that both mechanical properties and permeability are highly dependent on stress because of the hyperbolic nature of the stiffness of fractures, different closure behavior of fractures, and change of fluid pathways caused by deformation. This study shows that proper characterization and consideration of in-situ stress are important not only for boundary conditions of a selected site but also for the understanding of the mechanical and hydraulic behavior of fractured rocks.
Keywords
Discrete Fracture Network (DFN); Discrete Element Method (DEM); Equivalent Mechanical Properties; Equivalent Hydraulic Property; In-situ stress;
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