在内河中修建沉管基槽后,水流经过基槽时,泥沙会在基槽内部形成淤积。为研究基槽内回淤厚度分布规律,依托襄阳沉管隧道项目,采用观测分析与数值模拟相结合的方法,得到短期沉管基槽内不同位置回淤厚度,探析沉管下放前后对回淤厚度的影响。研究表明:在基槽垂线方向上,泥沙浓度随着水深增加而增加;水流经过基槽时,流速减弱造成挟沙能力下降,回淤主要集中在基槽前坡和基槽内,在基槽后坡回淤厚度较小。在安装沉管后,基槽过流面积减小,在沉管底部回淤厚度比顶部回淤厚度要大。研究成果揭示了河流中挟沙水流在基槽内回淤厚度分布规律,可为相似工程提供借鉴。
Abstract
Following the construction of immersed tube base groove in inland river, the flow of water through the groove leads to the deposition of silt within it. To obtain the distribution of silting thickness in tube base groove, this paper focuses on the Xiangyang immersed tube tunnel project. By combining observation with numerical simulation, we obtain the silting thickness of the base groove at different positions, and examine the influence of sediment concentration in the river on the silting thickness in tube base groove. Results demonstrate that sediment concentration in the direction vertical to the groove increases as the water depth increases. As water flows through the groove, the reduced flow velocity results in a decreased sediment carrying capacity. Consequently, the silting is mainly concentrated in the front slope and the base groove, whereas the thickness of silting is minimal in the back slope of the groove. After the installation of immersed tube, the flow area of the groove decreases, leading to a larger silting thickness at the bottom of the immersed tube compared to the top.
关键词
回淤厚度 /
泥沙浓度 /
沉管基槽 /
冲淤地形 /
流场分布
Key words
silting thickness /
sediment concentration /
immersed tube base groove /
scour and siltation terrain /
flow field distribution
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参考文献
[1] DISSANAYAKE D M P K,ROELVINK J A,VAN DER WEGEN M. Modelled Channel Patterns in a Schematized Tidal Inlet[J].Coastal Engineering,2009,56(11/12):1069-1083.
[2] 曹影峰, 李兴高, 杨 益. 深中通道沉管隧道基槽回淤及边坡稳定性研究[J]. 岩土工程学报, 2020, 42(7): 1350-1358.
[3] 辛文杰,贾雨少,何 杰.港珠澳大桥沉管隧道试挖槽回淤特征分析[J].水利水运工程学报,2012(2):71-78.
[4] 曹慧江, 肖烈兵. 港珠澳大桥岛隧工程沉管基槽开挖回淤强度研究[J]. 水运工程, 2012(1): 12-17.
[5] 傅鹤林, 董子龙, 洪开荣, 等. 内河交汇处沉管隧道基槽回淤厚度研究[J]. 长江科学院院报, 2022, 39(10): 103-108.
[6] 许春阳, 罗 雯, 陈永平, 等. 细颗粒泥沙制约沉降速度计算方法综述[J]. 泥沙研究, 2022, 47(1):73-80.
[7] 李慧梅,陈建国,袁玉萍.高含沙浑水在絮凝剂作用下的絮凝沉降试验研究[J].泥沙研究,2006(4):73-77.
[8] 刘俊秀,吉祖稳,王党伟. 黏性细颗粒泥沙絮凝试验研究综述[J]. 泥沙研究,2019,44(2):63-68.
[9] 黄 颖. 水库下游河床调整及防护措施研究[D]. 武汉: 武汉大学,2005.
[10] 黄才安. 冲积河流水流泥沙运动基本规律的研究[D]. 南京: 河海大学,2003.
[11] 周 双. 推移质泥沙随机起动与输移机理研究[D]. 杨凌: 西北农林科技大学,2021.
[12] 钱七虎. 从河床冲淤分析沉管法修建长江水下隧道问题[J]. 现代隧道技术, 2006, 43(4): 1-4.
[13] 陈雄波. 挟沙水流数值模拟中若干关键技术的研究[D]. 南京: 河海大学, 2004.
[14] 白 静. 悬移质泥沙输移的大涡模拟研究[D]. 北京: 清华大学,2013 .
[15] 孟 震. 推移质运动基本规律研究[D]. 北京: 清华大学, 2015 .
[16] 谢鉴衡.河流泥沙工程学(上册)[M]. 北京:水利电力出版社,1981.
[17] 沙玉清.泥沙运动的基本规律:开动流速[J]. 泥沙研究,1956(2):14-25.
[18] TE SLAA S, VAN MAREN D S, HE Q, et al. Hindered Settling of Silt[J]. Journal of Hydraulic Engineering, 2015, 141(9): 1-13.
[19] BALDOCK T E, TOMKINS M R, NIELSEN P, et al. Settling Velocity of Sediments at High Concentrations[J]. Coastal Engineering,2004,51(1):91-100.
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