Analysis of seepage in the conditions of increased reservoir capacity by raising the spillway level (Case study: Kamal-Saleh earth dam)

Document Type : Research Article

Authors

1 Arak university

2 Department of Civil, Faculty of Engineering, Arak University, Arak, Iran

3 Deputy of Planning and Development, Regional Water Company of Markazi, Arak, Iran

Abstract

Seepage is one of the main threats to the stability of the earth dam, which can weaken the dam structure and cause piping, washing the earth dam materials inside the body or foundation and eventually its failure. In this study, seepage analysis of Kamal-Saleh earth dam was performed using Seep/W software under three conditions of steady-state, rapid drawdown and end of construction for the current dam as well as for increased spillway level in stable seepage condition. The effect of increasing the height of spillway on the seepage rate inside the body and foundation of the dam, hydraulic gradient and phreatic surface was investigated. To evaluate the dam behavior in the conditions of increasing reservoir capacity, seepage analysis was performed for the current level and increased levels of spillway by one-meter intervals. According to the software results, the dam was safe against seepage in the current spillway level in every three conditions and provided the required factors of safety. In the conditions of increased spillway level, the amounts of seepage and the hydraulic gradients increased and the factors of safety against boiling decreased in a way that by increasing the dam spillway level equal to 4 meters, the seepage through the dam body and foundation increased 85% and the safety factor against boiling decreased 4.5% but in all these conditions, the dam was safe against boiling. In the current and increased levels of the spillway, there are the appropriate similarity of phreatic lines produced by the selected analytical method and Seep/W.  The most similarity is seen in the upstream shell and core and the maximum difference is seen in the phreatic line intersection with the downstream slope of the dam.

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[1]  H. Rahimi, Embankment Dams, Tehran University, Iran, 2013 (in persian).
[2]  H. Karimian Aliabad, Explaining the Elevation Method in Dam Cure, A Case Study of the Fusegate System in Zarrineh Rood Dam, M.Sc. Thesis in hydraulic structures, Shahid Chamran Ahvaz university, Iran, 2010  (in persian).
[3]  M. Yazdanian, H.R. Afshoon, S. Ghasemi, V. Afshoon, F. Fahim, Effect of Height on the Static Stability of Heterogeneous Embankment Dams, Journal of Engineering ,Science and Technology, 5(3) (2017) 274-282.
[4]  X.G. Song, Z.D. Zhou, H.B. Zhang, H.Y. Yue, Study on the Capacity Increasing and Dam Heighten of Plain Reservoirs, Journal of Applied Mechanics and Materials, 353-356 (2013) 2531-2536.
[5]   M.S.B. Gorgi, Feasibility Study for Increasing the Height of the Golgestan Earth Dam by Finite Element Method, Second National Conference on New Research Findings in Civil Engineering, Architecture and Urban Planning, 2016  (in persian).
[6]  A. Abdulsattar, M. Faris, A. Zedan, Seepage Analysis through an Earth Dam (KHASA-CHAI Dam) as a Case Study, Journal of Engineering and Technology, 35(2 Part (A) Engineering) (2017) 172-181.
[7]  H.H. Fazlollah Soltani, N. Irani and M. Zeinodini Moghaddam, Investigation of discharge of earth dam in unsaturated state with reservoir volume fluctuations using Rawls et al (1982) and Casrel and Parrish (1988) methods Case Study of Maneciu Dam, International Conference on Civil Engineering, Tehran, 2016  (in persian).
[8]  M.W. Stello, Seepage charts for homogeneous and zoned embankments, Journal of geotechnical engineering, 113(9) (1987) 996-1012.
[9]   M.A.E.M. Rezk, Earth dam with an internal core, Journal of Alexandria Engineering, 34 (1995).
[10]  M.A.E.-R.M. Rezk, A.E.-A.A.A. Senoon, Analytical solution of seepage through earth dam with an internal core, Journal of Alexandria Engineering, 50(1) (2011) 111-115.
[11]  F. Kasim, W.S. Fei, Numerical parametric simulations for seepage flow behaviour through an earthfill Dam, Malaysian Journal of Civil Engineering, 14(1) (2002).
[12]  A. Zomorodian, S.M. Abodollahzadeh, Effect of horizontal drains on upstream slope stability during rapid drawdown condition, International Journal of Geology, 4(4) (2010) 85-90.
[13]  K. S Ismaeel, B.M. Noori, Evaluation of seepage and stability of duhok dam, in:  AL-Rafdain Engineering Journal (AREJ), 2011, pp. 42-58.
[14]  C. Andreea, Unsaturated Slope Stability and Seepage Analysis of a Dam, Energy Procedia, 85 (2016) 93-98.
[15]  H. Hasani, J. Mamizadeh, H. Karimi, Stability of slope and seepage analysis in earth fills dams using numerical models (Case Study: Ilam Dam-Iran), Journal of World Applied Sciences, 21(9) (2013) 1398-1402.
[16]  M.M. Sazzad, M. Roy, M.S. Rahman, FEM Based Seepage Analysis through Earth Dam, International Journal of Advances in Structural and Geotechnical Engineering, 4(3) (2015) 158-164.
 [17]  S. Al-Labban, Seepage and Stability Analysis of the Earth Dams under Drawdown Conditions by using the Finite Element Method, Ph.D. Thesis in civil engineering, University of Central Florida, America  (2018).
[18]  M.Y. Fattah, H.A. Omran, M.A. Hassan, Behavior of an Earth Dam during Rapid Drawdown of Water in Reservoir–Case Study, International Journal of Advanced Research (2015), 3(10) (2015) 110-122.
[19]  L.C.E. Company, Geotechnical reports of Kamal Saleh Dam, Regional Water Authority of Markazi-Arak Province, 2010  (in persian).
[20]  Y. Li, C. Zhang, C. Chen, H. Chen, Calculation of Capillary Rise Height of Soils by SWCC Model, Journal of Advances in Civil Engineering, 2018 (2018).