长江中游牯牛沙水道整治后滩槽演变对水沙条件的响应  

Response of channel-floodplain evolution to water-sediment conditions after regulation at Guniusha Waterway in the mid reach of the Yangtze River

作　　者：韩飞 

机构地区：[1]长江航道局,武汉430010

出　　处：《水道港口》2016年第4期392-398,共7页Journal of Waterway and Harbor

摘　　要：以牯牛沙水道为研究对象,探讨三峡工程、航道整治工程作用下滩槽演变对水沙条件响应关系,阐明新治理目标下浅区碍航特性。主要结论为:三峡水库蓄水初期牯牛沙边滩演变规律为"洪季冲刷,枯季淤积",其滩体面积、宽度与汛后退水期天数为正相关关系;伴随汛后退水期缩短和输沙量的减少,牯牛沙边滩冲刷速率加快,在航道整治工程实施后,边滩面积淤涨,枯水期水流集中冲刷浅区,航道条件得到改善;在6.0 m×200 m航道尺度规划目标下,过渡段浅滩在汛后退水天数较短的年份,由于冲刷能力的减弱,进而出浅碍航;在一期和二期航道整治工程作用下牯牛沙边滩面积淤涨,但尾部窜沟仍有发育态势,航道边界条件仍不稳定;航道尺度提升过程中,仍需采取工程措施增强过渡段浅区冲刷动力,同时还需进一步增强滩体完整性和稳定性。This paper focused on the Guniusha Channel in the middle reaches of the Yangtze River, exploredthe evolution rules of shoals and channels under the combined action of many factors such as the operation of ThreeGorges Project and the channel improvement project, and thus gained an in-depth understanding of the navigationobstacle characteristics of the Guniusha Channel under the new governance goal. Main conclusion： after the im-poundment of the TGR, the point bar in the Guniusha Channel still followed the rules before the impoundment, i.e.,the scouring in flood season and the sedimentation in dry season, and the area（within the 0-m depth contour） andthe width were in proportion to the number of days in the water-falling stage after flooding; after the impoundment ofthe TGR, the water-falling stage after flooding was shortened, which was adverse to the maintaining of point bar pat-tern; meanwhile, the sharp decline in sediment discharge further accelerated the washout process of the point bar,and therefore, the first-stage channel improvement project was implemented; after the implementation of the chan-nel improvement project, the area of the point bar exhibited the siltation and the pattern of beach body was restoredto a certain degree; in dry season, the flow mainly scoured the shallow region in the transition section and improvedthe channel condition. If the channel dimension of the Guniusha Channel was increased to 6.0 m×200 m, a short wa-ter-falling period could reduce the flow ′ s scouring ability in the shallow region of the transition section, and there-fore the shallow region tended to be shallower and obstructed the navigation in adverse hydrologic years especiallyin the years with short water-falling stages after flooding. After the implementation of channel improvement mea-sures, although the point bar in Guniusha Channel exhibited the siltation, the chutes in the tail of the point bar weredeveloped, i.e., the boundary conditions of the Channel were still unstable. Therefore, with the aim of a

关 键 词：滩槽演变 水沙条件 碍航特性 响应关系 牯牛沙水道 

分 类 号：TV147[水利工程—水力学及河流动力学]