三峡水库变动回水区三角碛河段消落期维护疏浚方案

三峡水库175 m试验性蓄水以来,变动回水区典型河段出现了卵砾石淤积碍航的问题,其中又以三角碛河段表现尤为明显。三角碛河段位于重庆港区九龙坡港前沿,属于典型宽谷分汊浅滩,主航道弯、窄、浅、险。由于三峡水库蓄水引起泥沙冲淤规律变化,航道演变也出现新的特点,主航道泥沙淤积量不大,但对航道条件影响较大,消落期多次出现船舶搁浅事故。为改善三角碛河段消落期航道条件,对其实施维护性疏浚是很有必要的。通过实测资料分析,对三角碛河段泥沙冲淤变化特点进行研究,探讨疏浚设计方案,并分析疏浚效果。

Maintenance and dredging plans of Sanjiaoqi reach in fluctuating backwater area of the Three Gorges Reservoir

Since the 175 m test-operation of the Three Gorges Resevoir (TGR),the typical reach in the fluctuating backwater area has suffered navigation problems because of the pebble movements,among which the Sanjiaoqi reach is particularly serious.Located on the Jiulongpo harbor,Sanjiaoqi reach is a typical gully and branching reach,and the main channel is bend,narrow,shallow and dangerous.As a result of the change of the sediment movement law due to the impoundment of the TGR,new characteristics appear.The amount of sediment deposition is small,while the influence on the channel conditions is relatively large,and a lot of ships are stranded during the sluicing period.To improve the channel conditions,maintenance and dredging are extremely necessary.Based on the field measured data,we study the characteristics of sediment movements and discuss the dredging plan and effect.