Saturation recovery coefficient of nonuniform suspended sediment in the Jingjiang reach of the Middle Yangtze River

被引:0
|
作者
Li L. [1 ]
Xia J. [1 ]
Deng S. [1 ]
Zhou M. [1 ]
Li Z. [1 ]
机构
[1] State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan
来源
基金
中国国家自然科学基金;
关键词
Bed material composition; Saturation recovery coefficient; Stochastic process; Suspended load; The Middle Yangtze River;
D O I
10.14042/j.cnki.32.1309.2021.05.008
中图分类号
学科分类号
摘要
Sediment discharge in the Jingjiang reach has sharply reduced since the Three Gorges Project operation, and the channel has been scoured by the clear water in order to recover the sediment transport capacity. However, the recovery rate of nonuniform suspended sediment was different with the different bed material compositions along the Middle Yangtze River. Therefore, the equation of settling distance of nonuniform sediment is derived, based on the theories of Markov stochastic process and sediment motion. Then, according to the definition of saturation recovery coefficient (α) based on the diffusion theory of suspended sediment, the formula of grouped saturation recovery coefficient (αi) is modified using the equation of settling distance; However, it ignores the effect of bed material composition (BMC) on suspended sediment recovery. For the actual process of sediment transport in the Jingjiang reach, a formula of αi is then proposed with the effect of the BMC being considered. These results show that:① The value range of αi in this study was 0.12-0.27 at Shashi and Jianli when the influence of the BMC was not taken into account, but it became to the range of 0.000 3-0.171 8 and 0.003 5-0.157 9 respectively when considering the BMC effect; ② Among αi of different sediment groups, the relationship of αif for fine sediment>αim for medium sediment>αic for coarse sediment existed when the BMC effect was not considered, but the relationship of αif<αim<αic existed when considering the influence of BMC; and the recovery rate of suspended sediment at Shashi was higher than that at Jianli except for the recession period; ③ The variations of αi at Shashi and Jianli were sensitive to different groups during different periods, in which αi during the flood period was higher than the value during other periods. Through comparation and analysis, the proposed formula in this study can predict the value of αi for the Middle Yangtze River well, and it also providing a basis for further research on the recovery mechanism of suspended sediment in the reach downstream of the Three Gorges Dam. © 2021, Editorial Board of Advances in Water Science. All right reserved.
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页码:727 / 737
页数:10
相关论文
共 27 条
  • [1] LIU C, SUI J Y, HE Y, Et al., Changes in runoff and sediment load from major Chinese rivers to the Pacific Ocean over the period 1955-2010[J], International Journal of Sediment Research, 28, 4, pp. 486-495, (2013)
  • [2] LYU Y W, FAGHERAZZI S, ZHENG S, Et al., Enhanced hysteresis of suspended sediment transport in response to upstream damming:an example of the Middle Yangtze River downstream of the Three Gorges Dam[J], Earth Surface Processes and Landforms, 45, 8, pp. 1846-1859, (2020)
  • [3] ZHAO W Y, YANG Y P, ZHANG H Q, Et al., Adjustment patterns and causes of the morphology of sandy riverbed downstream of the Three Gorges Dam[J], Advances in Water Science, 31, 6, pp. 862-874, (2020)
  • [4] GUO X H, QU G, LIU Y, Et al., Sediment transport of different particle size groups in the downstream channel after operation of the Three Gorges Project, Journal of Lake Sciences, 32, 2, pp. 564-572, (2020)
  • [5] DOU G R., Suspended sediment movement and calculation of erosion and deposition in tidal flow, Journal of Hydraulic Engineering, 4, pp. 13-24, (1963)
  • [6] HAN Q W, CHEN X J., Theoretical method for calculating the saturation recovery coefficient, Journal of Sediment Research, 6, pp. 8-16, (2008)
  • [7] WANG X H, CAO R X, SHEN J., Investigation on coefficient of saturation recovery of non-uniform suspended load, Journal of Hydraulic Engineering, 34, 3, pp. 120-124, (2003)
  • [8] GE H, ZHU L L, ZHANG X B., Analysis of nonuniform sediment recovery coefficient downstream from reservoir, Engineering Journal of Wuhan University, 44, 6, pp. 711-714, (2011)
  • [9] HAN Q W., A study of the non-equilibrium transportation of non-uniform suspended load, Chinese Science Bulletin, 24, 17, pp. 804-808, (1979)
  • [10] ZHOU J J, LIN B N., 2-D Mathematical model for suspended sediment part I:model theories and validations[J], 应用基础与工程科学学报, 3, 1, pp. 78-98, (1995)