To solve the problems of navigation obstruction,ship blockage and other problems at Taoyuan Hub,eliminate safety risks,and actively adapt to the development requirements of the Yuan River water transport channel,it is planned to build a new second-line ship lock on the right bank of Taoyuan Hub.This second-line ship lock is a reconstruction and expansion project,whose layout not only needs to meet the navigation requirements of ships,but also needs to take into account factors such as flood discharge capacity,impact on existing buildings,land expropriation and demolition,etc.The technical difficulty is much higher than that of a new construction project.Aiming at the plane layout scheme of the new second-line ship lock on the right bank site,this paper adopts the 1100 integral fixed bed physical model to study the navigable flow conditions in the entrance area of the approach channel and the flood discharge capacity of the river under 4 schemes,and finally determines the modification Scheme 4 as the final recommended scheme.The test results show that reducing the length of the barrier wall combined with the measures of riverbed dredging can effectively increase the flood discharge capacity of the river and reduce the water level after the implementation of the project.By adjusting the direction of the channel and the water flow,and extending the dredging depth,the transverse fall in the entrance area of the approach channel can be avoided and the backflow intensity in the entrance area can be reduced.By adding a short submerged dam,the flow to the approach channel can be reduced without affecting the flood discharge capacity of the channel,thus weakening the backflow intensity in the mouth area.The research results can provide reference for similar projects.