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http://dx.doi.org/10.9719/EEG.2020.53.3.271

Effect of Joint Geometry on Anisotropic Deformability of Jointed Rock Masses  

Ryu, Seongjin (Dept. of Energy Resources Engineering, Pukyong National University)
Um, Jeong-Gi (Dept. of Energy Resources Engineering, Pukyong National University)
Publication Information
Economic and Environmental Geology / v.53, no.3, 2020 , pp. 271-285 More about this Journal
Abstract
In this study, a numerical experiment related to the stress-strain analysis was performed on 3-D discrete fracture network(DFN) systems based on the distinct element method to evaluate the effect of joint geometry on deformability of jointed rock masses. Using one or two joint sets with deterministic orientation, a total of 12 3-D DFN blocks having 10m cube domain were generated with different joint density and size distribution. Directional deformation modulus of the DFN cube blocks were estimated along the axis directions of 3-D cartesian coordinate. In addition, deviatoric stress directions were chosen at every 30° of trend and plunge in 3-D for some DFN blocks to examine the variability of directional deformation modulus with respect to joint geometry. The directional deformation modulus of the DFN block were found to reduce with the increase of joint size distribution. The increase in joint density was less likely to have a significant effect on directional deformation modulus of the DFN block in case of the effect of rock bridges was relatively large because of short joint size distribution. It, however, was evaluated that the longer the joint size, the increase in the joint density had a more significant effect on the anisotropic deformation modulus of the DFN block. The variation of the anisotropic deformation modulus according to the variations in joint density and size distribution was highly dependent on the number of joint sets and their orientation in the DFN block. Finally, this study addressed a numerical procedure for stress-strain analysis of jointed rock masses considering joint geometry and discussed a methodology for practical application at the field scale.
Keywords
joint geometry; jointed rock mass; discrete fracture network; deformation modulus; distinct element method;
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Times Cited By KSCI : 2  (Citation Analysis)
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