Weituo water control project on the Fujiang River is located in a sharp bend section of a mountainous river.To address the problem that the upper approach channel and entrance area of the expanded ship lock are jointly affected by curved flow and dynamic-static water,resulting in strong oblique flow,we conduct physical model and ship model experiments to study the navigation conditions of the upper approach channel and entrance area under different layout schemes,and propose engineering measures to improve the navigation flow conditions.The results show that due to the influence of the water flow in the upstream bend,the flow velocity in the upper approach channel and its entrance area of the ship lock in the design scheme is relatively large,failing to meet the safety requirements for ships entering and exiting the ship lock under all navigable discharges.Through measures such as adding a division wall and submerged spur dike,excavating the riverbed on the opposite bank of the upper approach channel,translating the ship lock and adjusting the axis angle of the ship lock,all flow velocity indicators in the upper approach channel and area of the final modified scheme basically meet the specification requirements at Q≤5,000 m3/s.Combined with the ship model experiments results,ships can smoothly enter and exit the ship lock via the upper approach channel at Q≤5,000 m3/s.