长江上游钱口石梁滩切礁整治试验

钱口石梁是长江上游羊石盘—上白沙水道中水急滩。通过分析该滩段的碍航特性及滩险成因,采用模型试验方法对切礁整治方案进行研究。整治工程方案的影响因素包括切礁深度(4、5、6 m)、切礁范围(全部切除和部分切除)、弃渣填槽。结果表明:不同的切深方案,流态基本相同,横流减弱明显,基本不碍航;全部切除方案优势明显,航标数量减少,布设难度降低,航道维护和运行费用较小;弃渣填槽后,泡水和漩水一定程度减弱,流态进一步改善。推荐采用切礁深度5 m、全部切除,并将弃渣填槽的方案。方案实施后航道条件得到有效改善,航道维护难度和运行成本降低。

Tests for reef-cutting regulation of Qiankou rock ledge shoal in upstream reach of the Yangtze River

Qiankou rock ledge is one of the rapid shoals in the upper reaches of the Yangtze River.Based on the analysis of the reasons of navigation obstruction,we study the reef-cutting regulation by model tests.The influence factors of regulation project scheme consist of three depths (4,5 and 6 m) of reef-cutting,two levels (full blasting or partial one) of reef-cutting,and the reef filling tank.The results show that the different depth schemes have the basically same flow pattern,with transverse flow obviously weakened,and without obstruction of navigation.The full cutting scheme reduces the difficulty of navigation mark arrangement,decreases the number of the navigation mark,and reduces the maintenance and operation cost for this waterway section.So the advantages of this scheme are obvious.The bubble swirling water decreases to a certain extent and the flow pattern is further improved after reef-cutting.We recommend the scheme of channel regulation project of 5 m-depth and full reef-cutting blasting with the reef filling tank,because of the effective improvement of the waterway condition and the significant reduction of the waterway maintenance difficulty and operation cost.