长江上游叉鱼碛滩航道特性及维护对策

叉鱼碛为长江上游过渡段浅滩，位于泸州境内，属于天然河段。2013年向家坝水电站完成蓄水，2015年长江上游航道最小维护水深从2.7 m提高至2.9 m。2016年禁采前由于人为无序的挖砂采石对上游诸多滩段造成较大的破坏，枯水期水流分散，冲刷能力减弱。在诸多背景下，长江上游诸多碍航滩段枯水期航道畅通面临较大的挑战，叉鱼碛滩段为其中的一个代表。根据实测资料分析向家坝水电站蓄水前后水沙条件的变化，对滩段近年来的演变规律进行总结，并且根据近年航道维护疏浚实施情况、疏浚效果以及相关问题，对滩段的航道维护对策进行分析，为滩段养护疏浚的设计、施工提出相关建议以及加抛整治建筑物的治理方案，可为航道维护及航道治理提供技术支撑。

Channel characteristics and maintenance countermeasures of Chayuqi beach in upper reaches of the Yangtze River

Chayuqi is a transitional shoal in the upper reaches of the Yangtze River,located in Luzhou and belonging to the natural river section.In 2013,the Xiangjiaba Hydropower Station completed water storage,and in 2015,the minimum maintenance water depth of the upper reaches of Yangtze River waterway increased from 2.7 meters to 2.9 meters.Prior to the ban on mining in 2016,the disorderly excavation of sand and stones caused significant damage to many upstream beach sections,resulting in dispersed water flow and weakened erosion capacity during the dry season.Against various backgrounds,the smooth navigation of navigation channels in the upstream of the Yangtze River faces significant challenges during the dry season,and the Chayuqi shoal section is one of the representatives.This article analyzes the changes in water and sediment conditions before and after the impoundment of Xiangjiaba Hydropower Station based on measured data,summarizes the evolution laws of the beach section in recent years,and analyzes the maintenance and dredging strategies of the beach section based on the implementation of channel maintenance and dredging in recent years,dredging effects,and related issues.It provides relevant suggestions for the design and construction of the beach section maintenance and dredging,as well as the treatment plan for adding and disposing buildings,which can provide technical support for the future maintenance and management of the the beach section.