Experimental study of the consolidation of the cohesive sediments Case study: Karkheh dam reservoir

Document Type : Article

Authors

Department of Civil Engineering, Jundi-Shapur University of Technology, Dezful, Postal Code: 64616-18674, Iran

Abstract

The physical and chemical properties of cohesive sediments have been determined. The consolidation mechanism was also investigated in various scenarios by changing the initial sediment concentration from 50 to 150 gr/lit. In the experiments, cohesive sediment samples of the Karkheh dam reservoir were tested using settlement columns. The initial sediment concentration, initial settlement height, and temperature are among the effective parameters on the settlement of cohesive sediments. In addition, the effects of the bed elevation of reservoir, as well as the scale effects on the settlement of cohesive sediments, were also studied. The results showed that the initial free settlement process and the hindered settlement phase take more time than self-weight consolidation settlement stages by increasing initial sediment concentration. Therefore, at an initial sediment concentration of 25 g/l and 150 g/l, the samples began self-weight consolidation after 1.5 h and 17.5 h respectively. The results also showed that the final average concentration increased linearly by the initial concentration. The concentration of the settled sediments decreased with a nonlinear trend by the initial height. In addition, under the same initial conditions, by increasing the diameter of the settlement column, the final concentration of the settled sediments first decreased and then increased.

Keywords


References:
1. Tan, G. and Chen, Y. "Experimental study of cohesive sediment consolidation and its effect on seepage from dam foundations", International Journal of Sediment Research, 31(1), pp. 53-60 (2016).
2. Tan, G.M., Jiang, L., Shu, C.W., Ping, L.V., and Jun, W.A. "Experimental study of scour rate in consolidated cohesive sediment", Journal of Hydrodynamics, 22(1), pp. 51-57 (2010).
3. Fathi-Moghadam, M., Emamgholizadeh, S., Bina, M., and Ghomeshi, M. "Physical modelling of pressure flushing for desilting of non-cohesive sediment", Journal of Hydraulic Research, 48(4), pp. 509-514 (2010).
4. Mueller, E.R., Grams, P.E., Schmidt, J.C., Hazel, J.E., Alexander, J.S., and Kaplinski, M. "The influence of controlled floods on fine sediment storage in debris fan-affected canyons of the Colorado River basin", Geomorphology, 226, pp. 65-75 (2014).
5. Shadorvan, M., Lashkar-Ara, B., and Seyed Kaboli, H. "Assessment of the cohesive sediments fall velocity in Karkheh Dam reservoir", Irrigation Science Engineering, 41(2), pp. 211-224 (2018).
6. Lashkar-Ara, B. and Fatahi, M. "On the measurement of transverse shear stress in a rectangular open channel using an optimal Preston tube", Scientia Iranica, 27(1), pp. 57-67 (2020).
7. Lashkar-Ara, B., Kalantari, N., Khozani, Z.S., and Mosavi, A. "Assessing machine learning versus a mathematical model to estimate the transverse shear stress distribution in a rectangular channel", Mathematics, 9(6), 596 (2021).
8. Wu, W., Perera, C., Smith, J., and Sanchez, A. "Critical shear stress for erosion of sand and mud mixtures", Journal of Hydraulic Research, 56(1), pp. 96-110 (2017).
9. Mathew, R. and Winterwerp, J.C. "Surficial sediment erodibility from time-series measurements of suspended sediment concentrations: development and validation", Ocean Dynamic, 67(6), pp. 691-712 (2017).
10. Schoellhamer, D.H., Manning, A.J., and Work, P.A. "Erosion characteristics and horizontal variability for small erosion depths in the Sacramento-San Joaquin River Delta, California, USA", Ocean Dynamic, 67(6), pp. 799-811 (2017).
11. Khastar-Boroujeni, M., Esmaili, K., Samadi- Boroujeni, H., and Ziaei, A. "Wastewater effect on the deposition of cohesive sediment", Journal of Environmental Engineering, 144(1), p. 04017083 (2018).
12. Krishnappan, B.G. "Cohesive sediment transport studies using a rotating circular flume", 7th International Conference Hydroscience and Engineering, pp. 1-15 (2006).
13. Glasbergen, K., Stone, M., Krishnappan, B., Dixon, J., and Silins, U. "The effect of coarse gravel on cohesive sediment entrapment in an annular  flume", IAHS-AISH Proceedings and Reports, 367, pp. 157- 162 (2014).
14. Haralampides, K., McCorquodale, J.A., and Krishnappan, B.G. "Deposition properties of fine sediment", Journal of Hydraulic Engineering, 129(3), pp. 230-234 (2003).
15. Tran, D. and Strom, K. "Floc sizes and resuspension rates from fresh deposits: Influences of suspended sediment concentration, turbulence, and deposition time", Estuarine, Coastal and Shelf Science, 229, p.106397 (2019).
16. Guo, C., He, Q., Guo, L., and Winterwerp, J.C. "A study of in-situ sediment  occulation in the turbidity maxima of the Yangtze Estuary", Estuarine, Coastal and Shelf Science, 191, pp. 1-9 (2017).
17. Guo, C., He, Q., van Prooijen, B.C., Guo, L., Manning, A.J., and Bass, S. "Investigation of  occulation dynamics under changing hydrodynamic forcing on an intertidal mud at", Marine Geology, 395, pp. 120-132 (2018).
18. Li, F.G., Xiong, X.Z., and Zhao, M. "Basic characteristics of muddy water with high concentration", Yellow River, 2(4), pp. 31-32 (2006).
19. Tang, J., Wang, Y.P., Zhu, Q., Jia, J., Xiong, J., Cheng, P., Wu, H., Chen, D., and Wu, H. "Winter storms induced high suspended sediment concentration along the north offshore seabed of the Changjiang estuary", Estuarine, Coastal and Shelf Science, 228, p. 106351 (2019).
20. Taheri, Z., Esmaili, K., Samadi, H., and Khodashenas, S.R. "Experimental investigation of the effect of consolidation time on erosion rate of cohesive sediment", Irrigation Science Engineering, 43(2), pp. 171-186 (2020).
21. Guo, S.J., Zhang, F.H., Song, X.G., and Wang, B.T. "Deposited sediment settlement and consolidation mechanisms", Water Science and Engineering, 8(4), pp. 335-344 (2015).
22. Xu, C., Chen, Y., Pan, Y., and Yu, L. "The effects of  occulation on the entrainment of fluid mud layer", Estuarine, Coastal and Shelf Science, 240, p. 106784 (2020).
Volume 28, Issue 6 - Serial Number 6
Transactions on Civil Engineering (A)
November and December 2021
Pages 3072-3081
  • Receive Date: 04 November 2020
  • Revise Date: 04 February 2021
  • Accept Date: 13 September 2021