Effect of Joint Orientation Distribution on Hydraulic Behavior of the 2-D DFN System

- Journal title : Economic and Environmental Geology
- Volume 49, Issue 1, 2016, pp.31-41
- Publisher : The Korean Society of Economic and Environmental Geology
- DOI : 10.9719/EEG.2016.49.1.31

Title & Authors

Effect of Joint Orientation Distribution on Hydraulic Behavior of the 2-D DFN System

Han, Jisu; Um, Jeong-Gi;

Han, Jisu; Um, Jeong-Gi;

Abstract

A program code was developed to calculate block hydraulic conductivity of the 2-D DFN(discrete fracture network) system based on equivalent pipe network, and implemented to examine the effect of joint orientation distribution on the hydraulic characteristics of fractured rock masses through numerical experiments. A rock block of size was used to generate the DFN systems using two joint sets with fixed input parameters of joint frequency and gamma distributed joint size, and various normal distributed joint trend. DFN blocks of size were selected from center of the blocks to avoid boundary effect. Twelve fluid flow directions were chosen every starting at . The directional block conductivity including the theoretical block conductivity, principal conductivity tensor and average block conductivity were estimated for generated 180 2-D DFN blocks. The effect of joint orientation distribution on block hydraulic conductivity and chance for the equivalent continuum behavior of the 2-D DFN system were found to increase with the decrease of mean intersection angle of the two joint sets. The effect of variability of joint orientation on block hydraulic conductivity could not be ignored for the DFN having low intersection angle between two joint sets.

Keywords

fractured rock mass;joint orientation distribution;discrete fracture network;block hydraulic conductivity;numerical analysis;

Language

Korean

Cited by

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