| 摘要: |
| 为解决长江口底沙输沙无实测资料的问题,研究南槽的底沙输移特性和航道回淤特征,本文基于坑测法原理开发了一套适用于长江口水沙环境的底沙输移监测系统,取得可靠的低扰动下南槽拦门沙段底沙输沙过程资料。观测结果显示,在潮周期过程中,输沙率与水动力强度大小密切相关,输沙率最大值一般出现在涨急时刻。涨落潮过程中,同样流速条件下,输沙率存在一定差异,涨潮时段推移质输沙率普遍大于落潮时段。根据窦国仁公式计算的单宽推移质输沙率与实测值相比在量级上基本一致,但仍有数倍的差距,天然测得的底沙输沙强度普遍大于窦国仁推移质输沙率公式的理论计算结果,公式推荐的输沙综合系数在长江口地区的适用性需要进一步探求。 |
| 关键词: 长江口南槽 推移质输沙率 潮周期过程 坑测法 |
| DOI： |
| 分类号:TV856 |
| 基金项目:长江口南槽底沙输沙率研究(Y222001)；长江口水源地突发环境污染预警响应研究(Y222012) |
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| Observation and research on bedload transport at South Passage of Yangtze Estuary |
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DING Hongwei1, HAN Yufang1, Zhao Riming2, LU Chuanteng1, Xin Wenjie2, Hu Guodong3, Xie Zhizheng2
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1.River Harbor Engineering Department,Nanjing Hydraulic Research Institute;2.Nanjing Hydraulic Research Institute;3.Survey Bureau of Hydrology and Water Resources of the Changjiang River Estuary
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| Abstract: |
| In order to solve the problem of lacking measurement data on bedload transport at Yangtze Estuary and study the characteristics of bedload transport and channel siltation at South Passage, this paper developed a kind of bedload transport monitoring system based on the principle of pit measurement and obtained reliable data on the bedload transport process at the entrance bar of South Passage under low disturbance. The observation results showed that the bedload transport rate was closely related to the hydrodynamic magnitude, while the maximum bedload transport rate generally occurred at the time of maximum flood during the tidal cycle. On the same flow velocity conditions, there were some differences in bedload transport rate, and the bedload transport rate during flood tide was generally greater than that during ebb tide. The single-width bedload transport rate calculated according to Dou"s formula was basically consistent with the measured value in magnitude, but there was still a several-fold difference. The natural measured bedload transport intensity was generally greater than Dou"s formula for bedload transport rate. Therefore, the applicability of the comprehensive coefficient recommended by the formula at Yangtze Estuary needs further exploration. |
| Key words: South Passage at Yangtze Estuary bedload transport rate tidal cycle process pit measurement method |
