JRC등급에 따른 절리면 수리특성 연구 = A Study on hydraulic characteristics of rock joints dependant on JRC ranges

다국어 초록 (Multilingual Abstract)

In order to characterize hydraulic property dependant on join roughness in rock mass, this study computed permeability coefficients on each range of joint roughness coefficient (JRC) suggested by Barton(1976). For a quantitative analysis of roughness components spectral analysis using the fast Fourier transform was performed to select effective frequencies on each JRC range. The results of spectral analyses show that low ranges of the JRC are mainly composed of low frequency domain, while high ranges of the JRC have dominant components at high frequency domain. The inverse Fourier transform made it possible to generate joint models of each JRC range using the effective frequencies of roughness spectrum. The homogenization analysis was applied to calculate permeability coefficient at homogeneous microscale, and then, computes a homogenized permeability coefficient (C-permeability coefficient) at macro scale. Therefore, it is possible to analyze accurate characteristics of permeability reflected with local effect of facture geometry. According to the calculation results, permeability coefficients were distributed between 10-3m/sec and 10-4m/sec. In cases of sheared joint models permeability coefficients were plotted between 10-4m/sec and 10-5m/sec, showing irregular distribution of permeability coefficients on each JRC range. The differences of permeability coefficients for the same aperture models or for the sheared joint models indicate that changes of roughness pattern influence on permeability coefficients. Therefore, the effect of joint roughness should be considered to characterize hydraulic properties in rock joints.

참고문헌 (Reference)

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