Numerical Simulation of Effect of Drain Pipe in Uplift Force, Exit Hydraulic Gradient and Seepage in Gravity Dams

Document Type : Research Article

Authors

1 Water Engineering Department, Faculty of Agriculture, University of Tabriz, Tabriz, Iran

2 Water and Science Enginreering, tabriz,tabriz,iran

Abstract

In this study, the effects of diameter and location of drain pipes in uplift force, exit hydraulic gradient and seepage in the foundation of gravity dams are investigated. For this purpose, the SEEP/W software as a subgroup of Geo-Studio software is implemented and the foundation of a gravity dam is simulated. The results showed that the existence of drain pipes under the gravity dam reduce 4, 6, and 9 times of uplift force, exit hydraulic gradient and seepage, respectively. Installation of two drain pipes with 0.25L distance from each other and in the depth of 0.26D near the dam heel presents a more suitable position with respect to uplift force reduction (D is the pervious foundation depth). Also, by defining the best position for the location of drain pipes, it was observed that drainage pipes in these situations reduce 41-67% in the volume of the studied dam and increase the safety factor up to 2 to 3 times against the dam overturning. It is also found that the drainage pipe diameter has less effect on the uplift force, exit hydraulic gradient and seepage and is controlled by the rules of the executive. For validation, the numerical method used in this study was compared with the laboratory method by others and a suitable match was observed.

Keywords

Main Subjects

References

[1] R.S. Varshney, Concrete Dams, Oxford and IBH Publishing CO. New Delhi, 1982.
[2] J. Abedi kopaye, Investigating effective factors in uplift pressure in sustainability of diversion dams Limited finite difference method, Tarbiat Modares University, 2001. (in Persian)
[3] B. Mansuri, F. Salmasi, B. Oghati, Effect of location and angle of cutoff wall on uplift pressure in diversion dam, Geotechnical and Geological Engineering, 32(4) (2014) 1165–1173.
[4] S. Azizi, F. Salmasi, A. Abbaspour, H. Arvanaghi, Weep hole and cut-off effect  in decreasing of uplift pressure (case study: Yusefkand Mahabad diversion dam, Journal of Civil Engineering and Urbanism, 2(3) (2012) 97-101.
[5] B. Nourani, F. Salmasi, A. Abbaspour, Numerical Investigation of Foundation Drains Performancein Decreasing Uplift Force of Concrete Gravity Dams, Journal of Water and Soil Science., 26(1/3) (2015) 113-125. (in Persian)
[6] M. Sedghi asl, , Effect of optimal position cutoff wall to reduce Seepage and flow velocity under hydraulic structure using the numerical model, in:  5th Iranian hydraulic conference, University of Kerman, 2005. (in Persian)
[7] B. Melvandi, , Investigating the behavior of deep drainage in reducing lifting force in concrete concrete weights by solving three-dimensional drainage equation, in:  6th Iranian Hydraulic Conference, Shahrekord Iran 2007.
[8] F. Salmasi, B. Nourani, B. Oghati, Numerical investigation of longitudinal drain effect under lined canal on uplift reduction, Hydrogeology, 1(2) (2017) 48-65. (in Persian)
 [9] F. Sayad zadeh, M.A. Zomorodian, Seepage analysis from layered soils using finite element method. .  , in:  6th Iranian hydraulic conference, Shahrekord University., 2007. (in Persian)
[10] M.S. Pakbaz, D. A., S. J., Evaluation of performance of plastic concert cutoff wall in Karkheh dam using 3-D Seepage analysis and measurement, Journal of Applied Sciences, 9(4) (2009) 724-730.
[11] R. Raymond, R.W. , V. E., Uplift Modeling for Fracture Mechanics Analysis of Concrete Dams, Journal of Structural Engineering ASCE,, 120(10) (1994) 3025-3044.
[12] A.S. Chawla, R. Thakur, K. Akhleash, , Optimum location of drain in concrete dams, Energy Engineering, ASCE, 116(7) (1990).
[13] M. Tofigh, A. Oria, Nonlinear analysis of unstable flow and Consolidation caused by Seepage using the finite volume method. , in:  Third national civil engineering congress, Tabriz University, 2007. (in Persian)
[14] Anonymous, Geo-Studio,Version 8.15.11236, User Manual. GEOSLOPE International, Calgary, in, Alberta, Canada, 2012.
[15]  S.Salehi Hafshejani, S.H. Esmailzade, G.H. Panahi and K. Esmaili, Optimization of the drain position to reduce the uplift force in the foundation of dams, Journal of Water and Soil Science (Science and Technology of Agriculture and Natural Resources), 22(4)( 2017) 143-154. (in Persian).
Amirkabir Journal of Civil Engineering
Volume 53, Issue 6
September 2021
Pages 2209-2230

Files

Share

How to cite

Statistics