三峡水库蓄水后荆江大堤险工段近岸河床演变分析

Evolvement of Riverbed Near Bank of Dangerous Reach along Jingjiang River Levee after the Impoundment of Three Gorges Reservoir

针对荆江大堤在防洪减灾方面的重要性,选取荆江大堤沙市、盐观和郝龙3个重点险工段,根据三峡水库蓄水初期护岸监测资料,统计险工段典型冲刷坑的特征,分析了三峡水库蓄水后险工段近岸河床年际、年内演变特点及其影响因素,全面概括了三峡水库蓄水后险工状况。研究表明:三峡水库蓄水后荆江大堤险工段近岸河床普遍表现为近岸岸坡冲刷、水下岸坡变陡,最低点高程降低,且各险工段近岸河床演变规律不同。

Jingjiang river levee is of great importance for flood control and disaster reduction. According to field data of bank protection during the initial impoundment of Three Gorges Reservoir （TGR） , we analyzed the interannual and annual variations and their inducing factors for riverbed near the bank of dangerous reaches after the TGR impoundment. We also summarized the status of dangerous reaches after the TGR impoundment. Three typical bank revetment reaches, Shashi, Yanguan and Haolong, are selected for case study. Research results show that most of the bank slopes were scoured and steepened, the lowest elevation decreased, and the characteristics of riverbed evolvement are not identical in different dangerous reaches along Jingjiang River levee.