Numerical study of 3D passive earth pressure on a rigid retaining wall in three displacement modes

When the width to depth ratio of a retaining structure in an actual project is small, there is an obvious 3D effect of the passive earth pressure on the retaining wall. Therefore, the study of the 3D passive earth pressure on the retaining wall is of great significance. In this study, a numerical model was established to study the 3D passive earth pressure on the rigid retaining wall in three displacement modes (i.e., translation, rotation around the bottom, and rotation around the top). In this regard, the 3D passive earth pressure coefficients in three displacement modes were obtained. The results showed that the displacement mode significantly affected the size and distribution of 3D passive earth pressure, the spatial effect of passive earth pressure gradually weakened with the increase of the width to depth ratio ( b/h ) of the retaining wall, and when b/h >10, the spatial effect of passive earth pressure could be ignored from the engineering point of view. We believe that the results of this research could provide a reference for the investigation of the 3D passive earth pressure on the retaining wall and other related engineering designs.