To investigate the impact of spur dike groups on water flow characteristics and local scour in the lower reach of the Luanhe River, a three-dimensional water and sediment model is constructed by using Flow 3D software. The model’s accuracy is validated using measured data in 2015. Simulations are conducted under both constant and unsteady flow conditions, considering 5-year and 10-year return periods, to analyze flow velocity distribution and local scour at groin head. Findings demonstrate that the spur dike group effectively reduces flow velocity, enhances river bank resistance to water erosion, and protects the river banks of Yaozhuang segment in the lower reaches of the Luanhe River. Under constant flow, the maximum velocity zone of the main stream gradually shifts towards the right bank during the 10-year return period, compared to the 5-year return period. Moreover, the velocity at groins impacted by the mainstream increases by approximately 1.7 m/s, while the flow velocity at the head of other groins rises by around 0.9 m/s. During flood discharge, typical groin head subjected to the mainstream experiences noticeable scour pits assuming a long and narrow strip shape aligned with the water flow direction. Additionally, with longer return periods, the depth of the scour pit at the head of a typical spur dike increases by about 1 m, and meanwhile the scour zone at groin head starts to propagate upstream.
Key words
spur dike group /
water and sediment model /
local scour /
hydraulic characteristic
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References
[1] GU Z P, AKAHORI R, IKEDA S.Study on the Transport of Suspended Sediment in an Open Channel Flow with Permeable Spur Dikes[J]. International Journal of Sediment Research, 2011(1):96-111.
[2] LI Z, WANG P, YANG W, et al. Geometric Characteristics of Spur Dike Scour under Clear-Water Scour Conditions[J]. Water,2018,10(6),doi: 10.3390/w10060680.
[3] PANDEY M, VALYRAKIS M, QI M,et al. Experimental Assessment and Prediction of Temporal Scour Depth Around a Spur Dike[J]. International Journal of Sediment Research, 2021, 36(1):22-33.
[4] ZYAMAN C, YERDELEN C, ERIS E, et al. Experimental Investigation of Scouring Around a Single Spur under Clear Water Conditions[J]. Water Supply, 2022, 22(3):3484-3497.
[5] HAJIBEHZAD M S, BEJESTAN M S, FERRO V. Investigating the Performance of Enhanced Permeable Groins in Series[J]. Water,2020,12(12),doi: 10.3390/w12123531.
[6] 喻 涛,王平义,陈 里,等.非恒定流作用下丁坝局部冲刷研究[J].四川大学学报(工程科学版),2014,46(3):31-36.
[7] 张林忠, 刘 燕, 万 强, 等. 黄河宁夏青石河段丁坝间距研究[J]. 人民黄河, 2018,40(11):49-52.
[8] LIAO C T , YEH K C , LAN Y C , et al. Improving the 2D Numerical Simulations on Local Scour Hole around Spur Dikes[J]. Water, 2021, 13(11),doi: 10.3390/w13111462.
[9] HAIDER R, QIAO D, WANG X, et al. Role of Grouped Piles on Flow Characteristics Around Impermeable Spur Dike[J]. International Journal of Civil Engineering, 2022, 20: 1-15.
[10] 胡志毅. 丁坝挑角对周围流场及局部冲刷影响的三维数值模拟研究[D]. 杨凌: 西北农林科技大学, 2021.
[11] 张 岩, 吴伊平, 崔鹏义, 等. 丁坝长度对弯道水力特性影响的数值模拟研究[J]. 水资源与水工程学报, 2019, 30(1): 164-170.
[12] 戚 蓝,曾庆达,吉顺文.天然河道丁坝群局部冲刷三维数值模拟[J]. 水利水运工程学报,2020(1):59-65.
[13] 吕庆标, 朱勇辉, 谢亚光, 等.河道崩岸机理研究进展[J].raybet体育在线
院报,2021, 38 (9): 7-13.
[14] 张小雅, 任春平, 杨帆.汾河二坝—义棠段液压坝群对河道冲淤变化影响的数值研究[J],raybet体育在线
院报,2023, 40 (8): 16-23.
[15] YAKHOT V, SMITH L M. The Renormalization Group, the Expansion and Derivation of Turbulence Models[J]. Journal of Scientific Computing, 1992,7(1):35-61.
[16] SOULSBY R. Dynamics of Marine Sand[M]. London: Thomas Telford Publications, 1997.
[17] MASTBERGEN D R, VAN DEN BERG J H. Breaching in Fine Sands and the Generation of Sustained Turbidity Currents in Submarine Canyons[J]. Sedimentology,2003, 50(4):625-637.
[18] 应 强. 丁坝水力学[M]. 北京: 海洋出版社, 2004.
[19] 李浩然.丁坝设计参数对坝体安全性的影响[D].西安:长安大学,2012.
[20] 范丽婵.长江中下游丁坝技术状况评价方法研究[D].南京:东南大学,2018.
[21] 栗铭阳, 张宝森, 方国华, 等. 基于Flow-3D的东安工程桩坝冲刷数值模拟研究[J]. 人民黄河, 2022,44(4):122-127.
[22] 王平义, 张继生, 程昌华. 航道整治建筑物安全稳定性的模糊综合评定[J]. 水动力学研究与进展A辑, 2004, 19(3): 83-388.