Active Earth Pressure of Finite Soil Based on Twin-Shear Unified Strength Theory

The influence of the intermediate principal stress was considered based on the twin-shear unified strength theory. The calculation of the finite width earth pressure is treated as a plane strain problem. By using the static equilibrium method under the flat slip surface assumption, an analytical solution of the active earth pressure was obtained under the plane strain state, and the results were compared to the actual measurement results obtained by previous studies to verify the feasibility of the proposed method. The relevant parameters under different intermediate principal stress influence coefficients are discussed based on calculation examples. The earth pressure calculation, with consideration to the influence of the intermediate principal stress, has theoretical significance and considerable economic benefits in engineering.