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신뢰성기법에 의한 굴착지반에서의 3차원 지하수 흐름해석

3-D Groundwater Flow Analysis of Excavated Ground by Reliability Method

  • 발행 : 2006.10.31

초록

지하수흐름에 대한 신뢰성 해석을 실시하였으며, 흐름에 관여하는 매개변수들이 목표 값의 파괴확률을 초과하는데 미치는 영향을 알아보았다. 본 연구를 위하여 2차원 지하수흐름 프로그램을 3-D 프로그램 DGU-FLOW로 확장하여 제작하고, 이를 1계 및 2계 신뢰성 프로그램에 연계하였다. 3차원 흐름 프로그램의 검증은 지하굴착지반의 지하수 흐름 해석 문제를 풀고 이를 MODFLOW 프로그램과 비교하여 수행하였다. 신뢰성부분 또한 몬테칼로 해석을 수행하여 나타난 파괴확률을 비교함으로써 검증하였으며 지하수 흐름에 대한 1계 및 2계 신뢰성해석을 수행하여 산정된 파괴확률 값은 몬테칼로 해석을 통하여 나온 값과 매우 근접하였다. 토질층의 투수계수에 대한 매개변수 해석결과 투수계수의 평균과 분산의 증가는 목표 수량을 초과하는 파괴확률의 증가를 가져오는 것으로 나타났다. 또한 파괴확률의 민감도는 여러흐름 변수중에서 흐름영역 경계부의 일정 수두에 가장 민감한 것으로 나타났다.

A reliability-groundwater flow analysis is performed and the influence of flow parameters on the probability of exceeding the threshold value is examined. For this study, the 3-D numerical groundwater flow program, DGU-FLOW, is developed by extending the 2-D flow program and is coupled to the first and second order reliability program. The 3-D flow program is verified by solving the examples of groundwater flow through the underground excavation and comparing the results from commercial MODFLOW program. Reliability routine of the program is also verified by comparing the probability of failure with that of Monte-Carlo Simulation. The reliability analysis of the groundwater flow showed that the probability of failure from the first and second order reliability method are quite close to that of Monte-Carlo Simulation. from the parametric study of hydraulic conductivity of soil layers, the increase of both mean and variance of hydraulic conductivity results in the increase of probability of exceeding the threshold flow quantity. The probability of failure was more sensitive to constant head located at the end of the flow domain than the other parameters.

키워드

참고문헌

  1. 장연수 (1995), '점토차수재를 통한 오염물질 이동에 대한 신뢰성 해석', 대한토목학회지, 제15권, 제5호, pp.1405-1416
  2. 정일문, 조원철, 허준행 (1998), '지하공동주변 매질의 불균일성을 고려한 수도의 불확실성 해석', 대한토목학회 학술발표회 논문집, 제3권, pp.41-44
  3. Bibby, R. and Sunada, D. K. (1971), 'Statistical Error Analysis of a Numerical Model of Confined Groundwater Flow', Proceedings of First International Symposium on Stochastic Hydraulics, C. L. Chiu, pp.591-612
  4. Dettinger, M. D., and Wilson, J. L. (1981), 'First-order Analysis of Uncertainty in Numerical Models of Groundwater Flow', 1, Mathematical development, Water Resource Research, Vol.17, No.1, pp.149-161 https://doi.org/10.1029/WR017i001p00149
  5. Gelhar, L. W. (1976), Stochastic Subsurface Hydrology, Prentice Hall, Englewood Cliffs, N.J
  6. Hachichi, W. (1981), Seepage-Related Reliability of Embankment Dams, Ph.D. Thesis, MIT, Cambridge, Massachusetts
  7. McMillan, W. D. (1966), 'Theoretical Analysis of Groundwater Basin Operations', Water Resource Center Contribution, Vol.114
  8. Sagar, B. and Kisiel, C. C. (1972), 'Limits of Deterministic Predictability of Saturated Flow Equations', Proceedings of Second Symposium on Fundamentals of Transport Phenomena in Porous Media, International Association Hydraulics Research, Guelph, Canada, Vol.1, pp. 194-205
  9. Sagar, B. (1978), 'Galerkin Finite Element Procedure for Analyzing Flow Through Random Media', Water Resources Research, Vol.14, No.6, pp.1035-1044 https://doi.org/10.1029/WR014i006p01035
  10. Sagar, B. and Clifton, P. M. (1984), 'Stochastic Groundwater Flow Modeling Using the Second-Order Method', RHO-SA-364P, Rockwell Handford Operations, Richland, Washington
  11. Shooman (1968), Probabilistic Reliability: An Engineering Approach, McGraw-Hill
  12. Sykes, J. F., J. L. Wilson and R. W. Andrews. (1985), 'Sensitivity Analysis for Steady-state Groundwater Flow using Adjoint Operators', Water Resources Research, Vol.21, No.3, pp.359-371 https://doi.org/10.1029/WR021i003p00359
  13. Townley, L. R., and J. L. Wilson. (1985), 'Computationally Efficient Algorithm for Parameter Estimation and Uncertainty Propagation in Numerical Models of Groundwater Flow', Water Resources Research, Vol.21, No.12, pp.1851-1860 https://doi.org/10.1029/WR021i012p01851
  14. Warren, J. E., Skiba, F. F., and Price, H. S. (1961), 'An Evaluation of the Significance of Permeability Measurements', Journal of Petrol. Tech., Vol.13, pp.739-744 https://doi.org/10.2118/1641-G-PA