曹娥江大闸闸下淤积现状分析及减淤对策初探

Exploration on the Siltation Situations and Countermeasures for Its Reduction at the Downstream of Cao’e river Barrage

曹娥江大闸系我国已建的潮汐河口最大挡潮闸,闸下淤积对大闸运行安全非常重要。试运行期的闸下河床高程主要取决于口外钱塘江尖山河道主槽位置,此外还受水闸泄水及钱塘江径流、潮流等众多因素影响。闸下冲刷主要受大闸泄水直接影响,无下泄条件下,闸下滩地高程受尖山河段河势控制。试运行期主槽靠南岸,闸下滩地较低,大闸泄流冲刷效果不明显。在对闸下冲淤分析的基础上,初步探讨了闸下减淤的对策。

Cao＇e river barrage was the largest in the alreadybuilt barrages of tidal estuaries in China. During its trial operation period, siltation at the downstream of the barrage was very important for the safety operation of barrage. The riverbed height at the downstream of the barrage depended on the location of main trough of Jianshan river channel in Qiantang estuary, and influenced by several factors like discharge of the barrage, rtmoff and tidal current of Qiantang river. The scouring at the downstream of the barrage was directly affected by discharge of the barrage. Under undrained conditions, the height of shoal at the downstream of the barrage was controlled by the river regime of Jianshan reach. During its trial operation period, the main trough was close to the south bank, the shoal at the downstream of the barrage was lower, and the effect of discharge scouring was not obvious. Based on the analysis of scouting and silting at the downstream of the barrage, this article elementarily discussed the siltation reduction at the downstream of the barrage.