Reliability Analysis of Seismic Stability of Gotvand Dam, Southwest of Iran

Document Type : Geotechnical Earthquake Engineering

Authors

1 Hayward Baker Inc., Nashville, USA

2 Shiraz University

3 California State Polytechnic University, Pomona

4 Shiraz University of Technology

5 Texas A&M Univ., College Station

Abstract

Seismic design of an embankment dam is a vital step in the design procedure of this important infrastructure. Deterministic approaches such as quasi-static and Newmark method have been employed to evaluate slope stability of embankmentdams. However, the variables required for a slope stability analysis, e.g. soil strength, pore pressure and loading parameters involve uncertainties which cannot be handled in the traditional deterministic methods. As an alternative, reliability analysis might be conducted to assess reliability indexes and the related failure probability of embankment dams. In this study, based on probability theories, a reliability analysis is performed to evaluate the seismic stability of an embankment dam (i.e., Gotvand dam) constructed in Iran. The probability of failure under seismic loading is considered for different sources of uncertainties involved in the problem, including uncertainty of loading, and the friction angle of core material as a strength parameter. Employing some statistical parameters, dynamic analysis is performed to determine the influence of friction angle variation on seismic slope stability. Significant pore pressure may build-up during cyclic loading, especially, when mixed clay (mixed clay and gravel) constitutes the dam core. Also, an undrained behavior of core materials has a great importance. Therefore, to estimate the effect of pore pressure build-up during seismic loading, two types of core materials (pure clay and mixed clay) are considered in this research. The results of dynamic analysis by finite element method are used to obtain the critical surface and acceleration in the embankment. Then, Newmark approach is employed to calculate the permanent displacement of the dam. Finally, reliability analysis is conducted and seismic performance of Gotvand dam during the earthquakes is investigated.

Keywords

References

  1. Ayyub, B.M. (1998) Uncertainty Modeling and Analysis in Civil Engineering. CRC Press, Boca
  2. Raton.
  3. Phoon, K.-K., and Ching, J. (2017) Risk and Reliability in Geotechnical Engineering. CRC
  4. Press.
  5. Beer, M., Zhang, Y., Quek, S.T., and Phoon, K.-K. (2013) Reliability analysis with scarce information: Comparing alternative approaches in a geotechnical engineering context. Struct. Saf.,
  6. , 1-10.
  7. Bea, R. (2006) Reliability and human factors in geotechnical engineering. J. Geotech. Geoenvironmental Eng., 132, 631-643.
  8. Ranganathan, R. (1990) Reliability Analysis and Design of Structures. Tata McGraw-Hill.
  9. Wolff, T.F. (1985) Analysis and Design of Embankment Dam Slopes: a Probabilistic Approach. Ph.D. Thesis, Purdue University.
  10. Tang, W.H., Yucemen, M.S., and Ang, A.H.-S. (1976) Probability-based short term design of soil slopes. Can. Geotech. J., 13, 201-215.
  11. Tobutt, D.C. (1982) Monte Carlo Simulation methods for slope stability. Comput. Geosci., 8, 199-208.
  12. Wang, Y., Cao, Z., and Au, S.-K. (2011) Practical reliability analysis of slope stability by advanced Monte Carlo simulations in a spreadsheet. Can.
  13. Geotech. J., 48, 162-172.
  14. Chowdhury, R.N. and Xu, D.W. (1994) Slope system reliability with general slip surfaces. Soils Found, 34, 99-105.
  15. Christian, J.T., Ladd, C.C., and Baecher, G.B. (1994) Reliability applied to slope stability analysis. J. Geotech. Eng., 120, 2180-2207.
  16. Al-Homoud, A.S. and Tahtamoni, W.W. (2000) Reliability analysis of three-dimensional dynamic slope stability and earthquake-induced permanent displacement. Soil Dyn. Earthq. Eng., 19, 91-114.
  17. Juang, C.H., Lee, D.H., and Sheu, C. (1992) Mapping slope failure potential using fuzzy sets. J. Geotech. Eng., 118, 475-494.
  18. Habibagahi, G. and Shahgholian, R. (2002) Reliability analysis of rock slopes using theory of fuzzy sets. Proc. of the 8th International Symposium on Numerical Models in Geomechanics, Rome, Italy, 547-551.
  19. Holtz, W.G. (1961). Triaxial shear characteristics of clayey gravel soils. Proc. of the Fifth International Congress on Soil Mechanics and Foundation Engineering, Paris, France, 143-149.
  20. Irfan, T.Y., and Tang, K.Y. (1992) Effect of the coarse fractions on the shear strength of colluvium. Geo Repor t 23, Geotechnical Engineering Office, Civil Engineering Dept., Hong Kong.
  21. Schultze, E. (1957) Large-scale shear tests. Proc.of the Fourth International Conference on Soil Mechanics and Foundation Engineering, London, UK, 193-199.
  22. Jafari, M.K. and Shafiee, A. (2004) Mechanical behavior of compacted composite clays. Can. Geotech. J., 41, 1152-1167.
  23. Seco e Pinto, P.S. (1993) Dynamic analysis of embankment dams. Proc. of the Seminar on Soil Dynamics and Geotechnical Earthquake Engineering, Lisbon, Portugal, A.A. Balkema, 159-269.
  24. Shafiee, A. (2008) Effect of core composition on seismic stability of earth dams. Proc. Inst. Civ. Eng. Geotech. Eng., 161, 283-290.
  25. Shafiee, A., Bahador, M., and Bahrami, R. (2008) Application of fuzzy Set theory to evaluate the effect of pore pressure build-up on the seismic stability of Karkheh Dam. Iran. J. Earthq. Eng., 12, 1296-1313.
  26. Cotecchia, V. (1987) Ear thquake-Prone Environments, in Slope Stability, Geotechnical Engineering and Geomorphology. John Wiley & Sons, Inc., New York, USA, 278-330.
  27. Kramer, S.L. (1996) Geotechnical Earthquake Engineering. Pearson, Upper Saddle River, N.J.
  28. Newmark, N.M. (1965) Effects of earthquakes on dams and embankments. Geotechnique, 15, 139-160.
  29. MGCE (1998) Technical Report on Foundation and the Body of Kharkheh Dam. Mahab Ghods Consulting Engineering Co. (MGCE), Tehran, Iran.
  30. MGCE (2005) Seismicity, Seismotechtonics and Seismic Hazard Analysis, Upper Gotvand Hydroelectric Dam Project . Iran Water & Power Resources Development Co. (IWPC), Tehran, Iran.
  31. Makdisi, F.I. and Seed, H.B. (1977) A Simplified Procedure for Estimating Earthquakeinduced Deformations in Dams and Embankments. College of Engineering, University of California, Earthquake Engineering Research Center.
  32. Jibson, R.W. (1993) Predicting earthquakeinduced landslide displacements using Newmark's sliding block analysis. Transp. Res. Rec., 9-17.
  33. Wilson, R.C. and Keefer, D.K. (1985) 'Predicting areal limits of earthquake-induced landsliding'. In: Evaluating Earthquake Hazards in the Los Angeles Region; An Earth-Science Perspective, J.I. Ziony (ed).
  34. Jones, A.L., Kramer, S.L., and Arduino, P. (2002) Estimation of Uncertainty in Geotechnical Properties for Per formance-Based Earthquake Engineer ing. Pacific Earthquake Engineering Research Center, Berkeley, USA.
  35. Mrabet, Z. (1999) Reliability Analysis of homogeneous earth fills-A new approach. Proc. of the 8th International Conference on Applications of Statistics and Probability in Civil Engineering, Sydney, Australia, Balkema, 499-507.
  36. Mrabet, Z. and Bouayed, A. (2000) Reducing uncertainty on the results of reliability analysis of earth fills using stochastic estimations. Proc.
  37. of the Second International Conference on Computer Simulation in Risk Analysis and Hazard Mitigation, Bologna, Italy, 203-214.
  38. Mrabet, Z. (2004) Some aspect on reliability in geotechnical engineering. Proc. of the 4th International Conference on Computer Simulation
  39. in Risk Analysis and Hazard Mitigation, Greece, 75-84.
  40. Spanos, P.D. and Ghanem, R. (1989) Stochastic Finite element expansion for random media. J. Eng. Mech., 115, 1035-1053.
  41. Fenton, G.A. (1990) Simulation and Analysis of Random Fields . Princeton University Princeton, NJ.
  42. Smith, I.M. and Griffiths, D.V. (1998) Programming the Finite Element Method. John Willey & Sons Ltd., West Sussex, UK.
  43. Mrabet, Z. (2002) Reliability analysis of earth fills using stochastic estimation methods. Proc. of 3rd International Conference on Mathematical
  44. Methods in Reliability, Trondheim, Norway, 17-20.
  45. Mrabet, Z. and Bouayed, A. (2003) Probabilistic risk assessment of homogeneous earth dams. Proc. of the 9th International Conference on Applications of Statistics and Probability in Civil Engineering, San Francisco, California, 367-372.
  46. Benjamin, J.R. and Cornell, C.A. (1970) Probability, Statistics, and Decision for Civil Engineers. McGraw-Hill, New York.
  47. ICOLD (1989) Selecting Seismic Parameters for Large Dams, Guidelines, Bulletin 72.

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