Journal of Hydraulic Structures

Journal of Hydraulic Structures

Adverse Effects of Repeated Deep Drawdown and Re-impounding Cycles on the Clay Core of Earth Dams; a case study of the Karkheh Dam

Document Type : Research Paper

Authors
Masoud Oulapour
Arash Adib
Sepideh Joulanejad
Deptartment of Civil Engineering, Faculty of Civil Engineering and Architecture, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
10.22055/jhs.2026.51342.1370
Abstract
In this study a method is proposed for investigation the effects of reservoir water-level fluctuations which results in wetting and drying cycles (WDC) in parts of the dam body. The WDC adversely affect the mechanical behavior of material in those parts, especially in semi-arid climatic areas, such as Iran. The degradation pattern of tested specimens is used for updating the material behaviour in numerical simulations of the Karkheh earth dam, located south-west of Iran. First the results of unconfined compressive strength (UCS) tests were simulated for calibration of the degradation pattern. Next, a sensitivity analysis was performed, which showed that cohesion is more effective than elastic modulus or friction angle. The degradation rates at each cycle were applied to the properties of dam core materials according to the WDC. The vertical and horizontal displacements of the dam were studied for a recorded reservoir level of 17 years in two cases of including the degradation or ignoring that. The results showed the difference between two cases growing up to about 10 %. This is a significant impact. Also, a series of simulations were conducted based on maximum and minimum permissible water level assumed for the next 7 years in both cases. The results showed that ignoring the degradation can result in up to 20% under estimating of the deformations. The results emphasize the necessity of further research on the subject.
Keywords
Embankment dams
Deep Drawdown
Drying-Wetting Cycles
Compressive Strength
Permeability Increase
Subjects
  1. Ri YN, Han UC, Jang UJ, Jong DY, Kim CU. Study on stability reduction characteristics of earth and rockfill dams under rapid drawdown using fully coupled seepage-stress analysis. Adv. Civ. Eng. 2022, 7954991. https://doi.org/10.1155/2022/7954991 .
  2. Meng Q, Qian K, Zhong L, Gu J, Li Y, Fan K, Yan L. Numerical analysis of slope stability under reservoir water level fluctuations using a FEM-LEM-combined method. Geofluids. 2020;6683311. https://doi.org/10.1155/2020/668331.
  3. Zhang J, Liu F, Yang Y, Zi Z, Ding Q, Wang G, Zhang W, Dai X, Liang Y, Liu G. Effects of dry–wet cycles on permeability and shear strength of Yuanmou red clay. Sustainability. 2025;17(19):8900. https://doi.org/10.3390/su17198900 .
  4. Talebolelm A, Khodashenas SR, Akhtarpour A. Investigation on effect of wetting and drying cycles on mechanical characteristics of clay materials. Iran J Irrig Drain. 2020; 14(3):1091-1105. (In Persian).
  5. Li J, Gao Y, Yang T, Zhang P, Deng W, Liu F. Effect of water on the rock strength and creep behavior of green mudstone. Geomech Geophys Geo-energ Geo-resour. 2023; 9:101. https://doi.org/10.1007/s40948-023-00638-9 .
  6. Salehiyan-Dastgerdi M, Hemmat A. Estimation of shear strength parameters of a fine-grained soil under cycles of wetting and drying. In: Proceedings of the 7th National Congress of Agricultural Machinery Engineering; 2013; Shiraz, Iran. (In Persian).
  7. de Costa PA, Mota JCA, Romero RE, Freire AG, Ferreira TO. Changes in soil pore network in response to twenty-three years of irrigation in a tropical semiarid pasture from northeast Brazil. Soil Tillage Res. 2014;137:23-32. https://doi.org/10.1016/j.still.2013.11.004
  8. Rogers LE, Wright SG. The effects of wetting and drying on the long-term shear strength parameters for compacted Beaumont clay. Center for Transportation Research, The University of Texas at Austin; 1986.
  9. Kholghifard M, Ahmad K, Ali N, Kassim A, Kalatehjari R. Collapse/swell potential of residual laterite soil due to wetting and drying-wetting cycles. Natl Acad Sci Lett. 2014; 37(2):147-153. https://doi.org/10.1007/s40009-013-0221-4.
  10. Wang G, Wei X. Modeling swelling–shrinkage behavior of compacted expansive soils during wetting–drying cycles. Can Geotech J. 2014;52(6):783-794 https://doi.org/10.1139/cgj-2014-0059.
  11. Kampala A, Horpibulsuk S, Prongmanee N, Chinkulkijniwat A. Influence of wet-dry cycles on compressive strength of calcium carbide residue–fly ash stabilized clay. J Mater Civ Eng. 2013;26(4):633-643. https://doi.org/10.1061/(ASCE)MT.1943-5533.0000853.
  12. Goh SG, Rahardjo H, Leong EC. Shear strength of unsaturated soils under multiple drying-wetting cycles. J Geotech Geoenviron Eng. 2013;140(2):06013001. https://10.1061/(ASCE)GT.1943-5606.0001032.
  13. Shi A, Yan N, Marschner P. Cumulative respiration in two drying and rewetting cycles depends on the number and distribution of moist days. Geoderma. 2015;243:168-174. https://doi.org/10.1016/j.geoderma.2014.12.019.
  14. Naramitkornburee A, Horpibulsuk S, Shen SL, Chinkulkijniwat A, Arulrajah A, Disfani MM. Durability against wetting–drying cycles of sustainable lightweight cellular cemented construction material comprising clay and fly ash wastes. Constr Build Mater. 2015;77:41-49. https://doi.org/10.1016/j.conbuildmat.2014.12.02.
  15. Du YJ, Bo YL, Jin F, Liu CY. Durability of reactive magnesia-activated slag-stabilized low plasticity clay subjected to drying–wetting cycle. Eur J Environ Civ Eng. 2016;20(2):215-230. http://dx.doi.org/10.1080/19648189.2015.1030088.
  16. Naeini SA, Gholampoor N, NajmosadatyYazdy SA. The effect of wetting-drying cycles and plasticity index on California bearing ratio of lime stabilized clays. J Eng Geol. 2015;9(2):2818. https://doi.org//10.18869/acadpub.jeg.9.2.2817.
  17. Wang B, Hu B. Dynamics of aggregate stability under drying and wetting cycles for yellow soil in China. 2016. Agro Environ:10th Int Symp Agriculture Environ.
  18. Sayem HM, Kong LW, Yin S. Effect of drying-wetting cycles on saturated shear strength of undisturbed residual soils. Am J Civil Eng. 2016;4(4):143-150. https://doi.org/10.11648/j.ajce.20160404.15.
  19. Tang CS, Wang DY, Shi B, Li J. Effect of wetting–drying cycles on profile mechanical behavior of soils with different initial conditions. Catena. 2016;139:105-116. https://dx.doi.org/10.1016/j.catena.2015.12.015.
  20. Wang DY, Tang CS, Cui YJ, Shi B, Li J. Effects of wetting–drying cycles on soil strength profile of a silty clay in micro-penetrometer tests. Eng Geol. 2016;206:60-70 https://dx.doi.org/10.1016/j.enggeo.2016.04.005.
  21. Akcanca F, Aytekin M. Impact of wetting–drying cycles on the hydraulic conductivity of liners made of lime-stabilized sand–bentonite mixtures for sanitary landfills. Environ Earth Sci. 2014;72(1):59-66. https://doi.org/10.1007/s12665-013-2936-4.
  22. Gallage C, Kodikara J, Uchimura T. Laboratory measurement of hydraulic conductivity functions of two unsaturated sandy soils during drying and wetting processes. Soils Found. 2013;53(3):417-430. https://doi.org/10.1016/j.sandf.2013.04.004.
  23. De Camillis M, Di Emidio G, Bezuijen A, Verástegui-Flores RD. Hydraulic conductivity and swelling ability of a polymer modified bentonite subjected to wet–dry cycles in seawater. Geotext Geomembranes. 2016. https://doi.org/10.1016/j.geotexmem.2016.05.007.
  24. Rosone M, Ferrari A, Celauro C. On the hydro-mechanical behaviour of a lime-treated embankment during wetting and drying cycles. Geomech Energy Environ. 2018;14:48-60. https://doi.org/10.1016/j.gete.2017.11.001.
  25. Liu W, Yang Q, Tang X, Yang G. Effect of drying and wetting on the shear strength of a low-plasticity clay with different initial dry densities. J Test Eval. 2015;44(4). https://doi.org/10.1520/JTE20140096.
  26. Luo SL, Huang D, Peng JB, Liu F, Gao XR, Tomas R. Influencing of drying-wetting cycles on mechanical behaviors of silty clay with different initial moisture content. Geomech Eng. 2024;38(3):307-317. https://doi.org/10.12989/gae.2024.38.3.307.
  27. Ma C, Li J, Jiao F, Liu Y, Feng H, Wang K, Jiang H, Jiang C, Li Y, Geng X. Physical and mechanical behaviors of compacted soils under hydraulic loading of wetting–drying cycles. Processes. 2023;11(4):1084. https://doi.org/10.3390/pr11041084.
  28. Cuisinier O, Masrouri F. Impact of wetting/drying cycles on the hydromechanical behaviour of a treated soil. E3S Web Conf. 2020;195:06008. https://doi.org/10.1051/e3sconf/202019506008 .
  29. Sabatino F, Cuisinier O, Russo G, Vitale E, Nicotera MV. Effects of wetting and drying cycles on the mechanical behaviour of lightweight cemented soils. E3S Web Conf. 2023;382:06008. https://doi.org/10.1051/e3sconf/202338206008 .
  30. Estabragh AR, Parsaei B, Javadi AA. Laboratory investigation of the effect of cyclic wetting and drying on the behaviour of an expansive soil. Soils Found. 2015;55(2):304-314. https://www.sciencedirect.com/science/article/pii/S003808061500027X
  31. Azizi A, Musso G, Jommi C. Effects of repeated hydraulic loads on microstructure and hydraulic behaviour of a compacted clayey silt. Can Geotech J. 2019. https://doi.org/10.1139/cgj-2018-0505 .
  32. Dias AS, Hughes PN, Toll DG. Soil–Water Retention Curve Prediction for Compacted London Clay Subjected to Moisture Cycles. Geotechnical and Geological Engineering. 2024;42(4):2799-2814. https://doi.org/10.1007/s10706-023-02706-z.
  33. Hafhouf I, Abbeche K. Impact of drying-wetting cycles on shear properties, suction, and collapse of sebkha soils. Heliyon. 2023;9:e13594. https://doi.org/10.1016/j.heliyon.2023.e13594.
  34. Walker C, Heitor A, Clarke BG. Impact of drying-wetting cycles on the small strain behaviour of compacted clay. Transp Geotech. 2023;42:101063. https://doi.org/10.1016/j.trgeo.2023.101063 .
  35. Oka F, Leroueil S, Tavenas F. A constitutive model for unsaturated compacted clays exhibiting cyclic wetting and drying. Soils Found. 1989;29(3):54. https://doi.org/10.3208/sandf1972.29.3_54.
  36. Prasomsri J, Takahashi A. Experimental study on suffusion under multiple seepages and its impact on undrained mechanical responses of gap‐graded soil. Soils Found. 2021;61(6):1660-1680. https://doi.org/10.1016/j.sandf.2021.10.003.
  37. Deng Z, Wang G, Jin W. Coupling of hydraulic loading and surcharge pressure during suffusion in sandy gravels. Geotechnique Lett. 2023;13(1):75-81. https://doi.org/10.1680/jgele.22.00130.
  38. Wang G, Deng ZZ, Yang J, Chen XS, Jin W. A large-scale high-pressure erosion apparatus for studying internal erosion in gravelly soils under horizontal seepage flow. Geotech Test J. 2022;45(6):1037-1053. https://doi.org/10.1520/gtj20220045 .
  39. Fu J, Yang Z, Sun Q, Xie Y, Yang J. Experimental and numerical investigation of seepage erosion in sandy cobbles under coupling hydraulic and dynamic load. Transp Geotech. 2024;49:101429. https://doi.org/10.1016/j.trgeo.2024.101429.
  40. Deng Z, Wang G, Wang Z, Jin W. Modelling erosion and stability degradation of a reservoir slope under periodic water level fluctuations. Comput Geotech. 2024;166:106021. https://doi.org/10.1016/j.compgeo.2023.106021.
  41. Liu D, Lin T, Gao J, Xue B, Yang J, Chen C, Zhang W, Sun W. Study on the influence of water level on earth dam reinforced by cut-off wall: a case study in Wujing Reservoir. Water. 2023;15:140. https://doi.org/10.3390/w15010140.
  42. Jadid R, Montoya BM, Bennett V, Gabr MA. Effect of repeated rise and fall of water level on seepage-induced deformation and related stability analysis of Princeville levee. Eng Geol. 2020;266:105458. https://doi.org/10.1016/j.enggeo.2019.105458.
  43. Liao K, Wu Y, Miao F. System reliability analysis of landslides subjected to fluctuation of reservoir water level: a case study in the Three Gorges Reservoir area, China. Bull Eng Geol Environ. 2022;81:225. https://doi.org/10.1007/s10064-021-02452-5.
  44. Chen J, Zhu Y, Lv L, Huang H. Influence of morphology of sliding surface on its seepage characteristics and slope stability under fluctuations in reservoir water level. Geotech Geol Eng. 2022;40:3211-3224. https://doi.org/10.1007/s10706-022-02087-9.
  45. Yang B, Yin K, Xiao T, Chen L, Du J. Annual variation of landslide stability under the effect of water level fluctuation and rainfall in the Three Gorges Reservoir, China. Environ Earth Sci. 2017;76:564. https://doi.org/10.1007/s12665-017-6929-7.
  46. Yang Z, Xi W, Yang Z, Shi Z, Huang G, Guo J, Yang D. Time-lag response of landslide to reservoir water level fluctuations during the storage period: a case study of Baihetan Reservoir. Water. 2023;15:2732. https://doi.org/10.3390/w15152732.
  47. Zhang Y, Zhang Z, Xue S, Wang R, Xiao M. Stability analysis of a typical landslide mass in the Three Gorges Reservoir under varying reservoir water levels. Environ Earth Sci. 2020; 79:243-254. https://doi.org/10.1007/s12665-020-08964-3.
  48. Haghdoost M, Lakzian E, Norouzi R, Abraham J, Sajjadi SM, Ahadiyan J. Numerical simulation using the finite element method to investigate the effect of internal cutoff walls on seepage and hydraulic gradients in homogeneous earth dams. Model. Earth Syst. Environ. 2023; 9:3851–3864. https://doi.org/10.1007/s40808-023-01755-w.
  49. Sadeghi HE, Ahadiyan J. Hydraulically Failure Mechanism of non-Cohesive Homogenous Protective Embankments by Overtopping, Irrigation Sciences and Engineering, 2018;41(1): 115-131. https://doi.org/10.1007/10.22055/jise.2018.13575. (In Persian).
  50. Panahi G. The effect of wetting and drying cycles on the physical properties of soil (A case study of Shahid Yaghoubi dam). Ferdowsi University of Mashhad. 2016.
  51. Mahab-e-Ghods Consulting Engineers. Karkheh dam Design- Detailed Design Phase Report, Technical Report. 1997. (In Persian)