Abstract: During the construction of high-grade channels in inland rivers, the new sheet piles and the original mortar block stone joint revetment have become a new revetment structure. The displacement of the original bank protection structures and the side earth pressure and the bending moment of the sheet piles are analyzed when there is no connection (J1) or rigid connection (J2) between the sheet piles and the original structures. The test results show that when the original structures are rigidly connected, the backward tilt and subsidence displacement are much smaller than those without connection, and the stability of the sheet piles is greatly improved. In the process of excavation under J1 and J2 conditions, there are translational and rotational displacements, while J1 is dominated by rotation, and J2 is dominated by translation. Influenced by the shape of the U-shaped sheet piles, soil arching is formed at both sides of the sheet piles during excavation, and the soil pressures on the sheet piles vary greatly at different positions at the same depth. In the process of excavation, the changes of the soil pressures in the range of the piles under J2 condition are consistent, and the variation range of the soil pressures at pile side increases with the increase of the pile depth under J1 condition. Under J1 condition, the maximum bending moment is located at the lower part of the piles, and under J2 condition, the maximum bending moment of J2 is greater than that of J1.