Engineering Geology

Engineering Geology

Narrow Canyon Effect on the Behavior of Earth Dams at the End of Construction (Case Study: Vanyar Dam)

Authors
1 Assistant Professor
2 Civil Engineer
Abstract
Earth dams are geotechnical structures constructed on various shapes of a valley. The Vanyar Dam is a rock-fill dam located on a narrow valley. Concerning the geometry of the canyon, three-dimensional modeling was utilized to analyze this dam. According to the numerical analysis, the maximum settlement is 88.14 cm, which corresponds to 48 m above the bedrock in cross-section C, that is, a little less than 1% of the dam height. Besides, the total vertical stresses recorded by the pressure cells are about 28% less than those obtained from the numerical analysis. It is assumed that the difference is caused by local arching due to lower compaction and consequently a low stiffness area around the pressure cells. In terms of pore water pressure, there is good agreement between the pore water pressure obtained from the numerical analysis and the piezometers, such that the results are restricted to less than 1%. In general, the difference between the numerical analysis results and those recorded by the instruments is acceptable. Furthermore, the dam shows a suitable level of performance at the end of construction.
Keywords

References
[1] Eisenstein Z, Krishayya AVG, Morgenstern NR. An analysis of cracking in earth dams, USAEWES Vickburg.miss: 1972, p. 431–545.
[2] Lefebvre G, Duncan JM, Wilson EL. Three-Dimensional Finite Element Analysis of Dams. J Soil Mech Found Div 1973;99(SM7):495–507.
[3] Belyakov AA. Three-dimensional behavior of an earth dam at a wide site. Hydrotechnical Constr 1988;22:718–25. doi:10.1007/BF01429609.
[4] Ohmachi T. A simplified 3–D FEM and its application to dynamic of fill dam in narrow canyons Vienna, Austria, 17-21 June. Seventeenth Int. Congr. Large Dams, Viena: 1991, p. 165–78.
[5] Stark TD, Eid HT. Performance of Three-Dimensional Slope Stability Methods in Practice. J Geotech Geoenvironmental Eng 1998;124:1049–60. doi:10.1061/(ASCE)1090-0241(1998)124:11(1049).
[6] Javaheri H. Three-dimensional dynamic analysis of Masjed-Soleyman rockfill dam. Sharif University of Technology, 1999.
[7] Heidari T. The Comparison of Three and Two Dimensional Dynamic Analyses of Earth Dams. Iran University of Science and Technology, 2003.
[8] Roth WH, Dawson EM, Somerville P, Davis CA, Plumb CC. Evaluation of the seismic performance of Stone Canyon dam with 2-D and 3-D analyses. 13th World Conf. Earthq. Eng., 2004, p. 1–6.
[9] Yu Y, Xie L, Zhang B. Stability of Earth-Rockfill Dams: Influence of Geometry on the Three-Dimensional Effect. Comput Geotech 2005;32:326–39.
[10] Yu Y, Zhang B, Yuan H. An intelligent displacement back-analysis method for earth-rockfill dams. Comput Geotech 2007;34:423–34.
[11] Qu G, Hinchberger SD, Lo KY. Case studies of three-dimensional effects on the behaviour of test embankments. Can Geotech J 2009;46:1356–70.
[12] Mahinroosta R, Alizadeh A, Gatmiri B. Simulation of collapse settlement of first filling in a high rockfill dam. Eng Geol 2015;187:32–44. doi:10.1016/j.enggeo.2014.12.013.
[13] Maddah A, Soroush A, Tabatabaie Shourijeh P. EEects of material properties on the behavior of embankment dam clay cores in narrow valleys. Sci Iranica 2015;22:1692–702.
[14] Gurbuz A, Peker I. Monitored Performance of a Concrete-Faced Sand-Gravel Dam. J Perform Constr Facil 2016;30:4016011. doi:10.1061/(ASCE)CF.1943-5509.0000870.
[15] Sukkarak R, Pramthawee P, Jongpradist P. A modified elastoplastic model with double yield surfaces and considering particle breakage for the settlement analysis of high rockfill dams. KSCE J Civ Eng 2016:1–12. doi:10.1007/s12205-016-0867-9.
[16] Derakhshandi M, Pourbagherian HR, Baziar MH, Shariatmadari N, Sadeghpour AH. Numerical analysis and monitoring of a rockfill dam at the end of construction (case study: Vanyar dam). Int J Civ Eng 2014;12:326–37.
[17] Mansouri H, Jorkesh Z, Ajalloeian R, Sadeghpour AH. Investigating effects of water salinity on geotechnical properties of fine-grained soil and quartz in a sandstone case study: Ajichay project in northwest Iran. Bull Eng Geol Environ 2017;76:1117–28. doi:10.1007/s10064-016-0920-4.
[18] Ghodsniroo Engineering Co. Technical reports of Vanyar dam. Tehran: Ghods-Niroo consultant engineers Co.; 2011.
[19] ITASCA. No Title. FLAC3D Version 30, Fast Lagrangian Anal Contin 3 Dimens 2005.
[20] Bergado DT, Teerawattanasuk C. 2D and 3D numerical simulations of reinforced embankments on soft ground. Geotextile and Geomembranes 2008;26:39–55. doi:10.1016/J.GEOTEXMEM.2007.03.003.
[21] Stark TD, Beaty MH, Byrne PM, Castro G, Walberg FC, Perlea VG, et al. Seismic deformation analysis of Tuttle Creek Dam. Can Geotech J 2012;49:323–43. doi:10.1139/t11-107.
[22] Qi C, Lu W, Wu J, Liu X. Application of Effective Stress Model to Analysis of Liquefaction and Seismic Performance of an Earth Dam in China. Math Probl Eng 2015;2015:1–7. doi:10.1155/2015/404712.
[23] Clough RW, Woodward RJ. Analysis of embankment stresses and deformations. J Soil Mech Found Div 1967;93(SM4):529–49.
[24] Gharti HN, Komatitsch D, Oye V, Martin  R, Tromp J. Application of an elastoplastic spectral-element method to 3D slope stability analysis. Int J Numer Methods Eng 2012;91:1–26. doi:10.1002/nme.3374.
[25] Ke W, Mingyue M, Dongxue H. Numerical analysis on mechanics of interaction between slurry and soil in earth dam by splitting grouted. Elsevier 2012;28:351–5.
[26] Cetin H, Laman M, Ertunç A. Settlement and slaking problems in the world’s fourth largest rock-fill dam, the Ataturk Dam in Turkey. Eng Geol 2000;56:225–42. doi:10.1016/S0013-7952(99)00049-6.
[27] Hunter GJ. The Pre-and Post-Failure Deformation Behaviour of Soil Slopes. The University of New South Wales, 2003.