Based on the Moshui ship lock,this paper studied the hydraulic characteristics of the loop culvert filling and emptying system by physical model tests with a geometric scale of 120.In view of the uneven outflow of the upstream lock head,a new and efficient T-type baffle beam was proposed;and the measure for enlarging the inlet dimension of the emptying culvert was put forward to improve the bad phenomena of penetrating funnel-shaped vortex at the inlet of the downstream lock head.The test results show that the maximum lateral mooring force can be reduced by 50% in the case of optimized energy dissipators,and various hydraulic indexes meet the requirements of the code.This study provides a scientific basis for the design of the Moshui ship lock,and can provide reference for the design of other loop culvert filling and emptying system ship locks.