长江中游宜都水道河床演变分析及治理对策初探

通过实测资料,系统分析了长江中游宜都水道演变特点,并重点对三峡蓄水后的演变规律进行了分析,提出初步治理对策。结果表明:宜都水道是长江中游离三峡枢纽最近、受其影响最早的碍航水道,天然情况下属枯季碍航浅水道;蓄水后,水浅的碍航问题得到了一定的改善,但其支汊发展、边滩冲刷现象明显,其对宜昌水位的控制作用受到威胁,因此及时实施该水道控导工程以稳定控制节点作用十分必要。

Fluvial feature and channel regulation strategy of Yidu reach in the middle Yangtze River

Based on field data,the features of fluvial process of the Yidu reach before and after the construction of the Three Gorges Project were discussed in this paper.It is found that the Yidu reach is immediately affected by the clear water released from the Three Gorges Project after dam impoundment.With the changes of sediment discharge,the shoal reach,which is obstructive to navigation before dam construction,has been scoured and the water depth increment is obvious.However,the erosion of anabranch and point bars have increased the area of cross section,so that the control effect of channel morphology on upstream water level is likely to take place.In order to prevent large changes of the water level at Yichang,it is proposed that some engineering practices should be put forward to prevent the sand bars from intensive erosion.