Silt deposition occurs in the downstream approach channel of the tidal lock as in a closed channel or excavated dock basin. It is often difficult to calculate or predict siltation because of complex flow and sediment ...Silt deposition occurs in the downstream approach channel of the tidal lock as in a closed channel or excavated dock basin. It is often difficult to calculate or predict siltation because of complex flow and sediment conditions and many other affecting factors. In this paper, the characteristics of flow movement in the approach channel (including its mouth) of the tidal lock are analyzed, the basic laws of sediment movement and siltation mechanism are investigated, the conditions for three types of siltation (circumfluence siltation, density flow siltation and slow flow siltation) are discussed, and corresponding calculating formulas are proposed. A practical example shows that the difference between measured and calculated results is small, indicating that the present calculating methods could be used in design and management of practical engineering projects.展开更多
曹娥江大闸口门船闸所在工程河段水文泥沙条件复杂,是兼具强涌潮、高含沙量、河床冲淤剧烈等特点的游荡型河段。针对高含沙量可能带来的闸下强淤积问题,通过曹娥江大闸闸下河床地形实测资料分析、冲淤现场试验、泥沙淤积计算等,总结河...曹娥江大闸口门船闸所在工程河段水文泥沙条件复杂,是兼具强涌潮、高含沙量、河床冲淤剧烈等特点的游荡型河段。针对高含沙量可能带来的闸下强淤积问题,通过曹娥江大闸闸下河床地形实测资料分析、冲淤现场试验、泥沙淤积计算等,总结河床冲淤规律,研究曹娥江大闸口门船闸水域河床稳定性等关键问题。根据现场冲淤试验分析,曹娥江大闸闸下115~200 m范围内在大潮淤积初期淤积速率为20.8~21.8 cm d,采用淤积经验公式计算得到口门船闸闸下淤积幅度可达17 cm d。对于闸下强淤积问题,提出蓄水冲沙池作为冲淤减淤方案,估算得到在蓄水冲沙池月均泄水量为813万m^(3)的情况下可使引航道河床维持约-1.7 m高程,为今后类似船闸的防淤减淤设计及科研提供参考。展开更多
文摘Silt deposition occurs in the downstream approach channel of the tidal lock as in a closed channel or excavated dock basin. It is often difficult to calculate or predict siltation because of complex flow and sediment conditions and many other affecting factors. In this paper, the characteristics of flow movement in the approach channel (including its mouth) of the tidal lock are analyzed, the basic laws of sediment movement and siltation mechanism are investigated, the conditions for three types of siltation (circumfluence siltation, density flow siltation and slow flow siltation) are discussed, and corresponding calculating formulas are proposed. A practical example shows that the difference between measured and calculated results is small, indicating that the present calculating methods could be used in design and management of practical engineering projects.
文摘曹娥江大闸口门船闸所在工程河段水文泥沙条件复杂,是兼具强涌潮、高含沙量、河床冲淤剧烈等特点的游荡型河段。针对高含沙量可能带来的闸下强淤积问题,通过曹娥江大闸闸下河床地形实测资料分析、冲淤现场试验、泥沙淤积计算等,总结河床冲淤规律,研究曹娥江大闸口门船闸水域河床稳定性等关键问题。根据现场冲淤试验分析,曹娥江大闸闸下115~200 m范围内在大潮淤积初期淤积速率为20.8~21.8 cm d,采用淤积经验公式计算得到口门船闸闸下淤积幅度可达17 cm d。对于闸下强淤积问题,提出蓄水冲沙池作为冲淤减淤方案,估算得到在蓄水冲沙池月均泄水量为813万m^(3)的情况下可使引航道河床维持约-1.7 m高程,为今后类似船闸的防淤减淤设计及科研提供参考。
