Characteristics of Block Hydraulic Conductivity of 2-D DFN System According to Block Size and Fracture Geometry

- Journal title : Tunnel and Underground Space
- Volume 25, Issue 5, 2015, pp.450-461
- Publisher : Korean Society for Rock Mechanics
- DOI : 10.7474/TUS.2015.25.5.450

Title & Authors

Characteristics of Block Hydraulic Conductivity of 2-D DFN System According to Block Size and Fracture Geometry

Han, Jisu; Um, Jeong-Gi;

Han, Jisu; Um, Jeong-Gi;

Abstract

Extensive numerical experiments have been carried out to investigate effect of block size and fracture geometry on hydraulic characteristics of fractured rock masses based on connected pipe flow in DFN systems. Using two fracture sets, a total of 72 2-D fracture configurations were generated with different combinations of fracture size distribution and deterministic fracture density. The directional block conductivity including the theoretical block conductivity, principal conductivity tensor and average block conductivity for each generated fracture network system were calculated using the 2-D equivalent pipe network method. There exist significant effects of block size, orientation, density and size of fractures in a fractured rock mass on its hydraulic behavior. We have been further verified that it is more difficult to reach the REV size for the fluid flow network with decreasing intersection angle of two fracture sets, fracture plane density and fracture size distribution.

Keywords

Fractured rock mass;Discrete fracture network;Block hydraulic conductivity;Representative elementary volume;

Language

Korean

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