三峡工程动工来葛洲坝水库河床演变分析

Analysis on River Bed Evolution of Gezhouba Reservoir Since the Starting of Three Gorges Project

根据葛洲坝水库固定断面资料，分析了三峡工程动工前葛洲坝水库河道演变情况和水库冲淤特性；重点分析了三峡工程动工６年来其河床演变情况。认为，三峡工程动工以来葛洲坝水库冲淤特性保持不变；三峡工程施工对河道的影响，主要集中在两坝之间．以一期工程施工期影响最大，大江截流以后情况好转；６年来，水库累计冲刷量为３６１６×１０４ｍ３，主要集中在常年回水区河段，其中两坝间累计冲刷量为２３２１．１×１０４ｍ３，１９９８年特大洪水是水库冲刷的主要原因。

Based on the fixed section information of Gezhouba reservoir, the paper analyses the feature ofevolution of the river bed and its scouring and silting before the starting of the Three Gorges Project and itfocuses on the evolution of the river bed since the starting of the Three Gorges Project for the last sixyears. The paper concludes that the feature of scouring and silting of Gezhouba reservoir remains unchanged;the influence of the project construction upon the river bed concentrates on the area between twodams, the first period of the construction had the greatest influence and then less after the river closure. Forthe last six years,the total amount of outwash is 3 616×104m3, concentrating on the river reach of permanent backwater,among which the total amount of outwash in the area between two dames is 2 321×104m3.98's flood is the major cause of the outwash of the reservoir.