Abstract: Arbitrary Lagrangian-Eulerian method is used to study large sloshing of water in large scale U-shaped aqueduct‚and to discuss the vibration responses of aqueduct structure with different water levels under sinusoidal loads and earthquake action．Analysis of the data indicates that nonlinear behaviors arise from the sloshing of free surface‚and become stronger with increase of the water level．Meanwhile‚under a certain water level‚the sloshing will increase suddenly． 

Key words: U-shaped aqueduct, arbitrary Lagrangian-Eulerian method, fluid-structure interaction, nonlinear sloshing