Abstract: The horizontal displacements of the retaining piles are monitored through the whole process of a deep excavation project. It is found that, due to the differences of horizontal bracing stiffness, the deformation modes of the retaining piles at different locations are different, and the maximum horizontal displacements also have significant differences. Through FEM modeling, the characteristics of the displacement fields caused by four deformation modes of retaining walls are analyzed. The results show that under the situations of different deformation modes of retaining structures with the same maximum horizontal displacement, the displacement fields of soils outside the excavation can be considerably different, and therefore the impacts on environment may vary greatly. In practical projects, besides controlling the maximum horizontal displacements of the retaining structures, the deformation mode of the retaining structures should be optimized according to the surrounding environment, and their kick-in deformation should be avoided.