Abstract: Friction at the contact surface between wall and soil is an important factor to be considered in analyzing the earth pressure of retaining wall. A novel method for analyzing the active earth pressure of retaining wall is proposed in consideration of the wall-soil friction based on static balance equation. First of all, the principal stress trajectory of soil behind the wall under the wall-soil friction effect is determined by studying the distribution of soil stress. On this basis, the trajectory is divided into curvilinear thin layers, and the change law of small principal stress of soil microelement is investigated. The method is verified with test data and compared with other methods. The sensitivity of active earth pressure coefficient to influential factors is also examined. Results demonstrate that the present method is rational and feasible as the distribution law of soil stress can be more accurately reflected by considering the stress deflection caused by wall-soil friction. The coefficient of active earth pressure reduces with the augment of internal friction angle φ of soil, while expands with the increment of friction angle δ between wall and soil.

Key words: retaining wall, active earth pressure, wall-soil friction, principal stress trajectory, curve layering