Active Earth Pressure against Rigid Retaining Walls for Finite Soils in Sloping Condition considering Shear Stress and Soil Arching Effect

摘要

The horizontal differential layer element method was used to study the active earth pressure of the finite-width soil formed by the rigid retaining wall for the embankment or adjacent foundation pits. The cohesionless soil was taken as the research object, and the soil arch theory was introduced based on the translation mode of rigid retaining wall and the linear sliding fracture surface. The minor principal stress line was assumed as circular, considering the deflected principal stress as soil arching effect. The shear stress between level soil layers in the failure wedge was calculated, and the differential level layer method was modified. Then, the theoretical formula of the active earth pressure, the resultant earth pressure, and the point of application of resultant earth pressure were obtained using this revised method. The predictions by the proposed formula were compared with the existing methods combined with the cases. It is shown that the resultant finite pressure increases gradually and approaches to Coulomb active earth pressure values when the soil is infinite, with the increase of the ratios of the backfill width to height. Moreover, the horizontal pressure for limited soils is distributed nonlinearly along the wall height. Considering the shear stress between level soil layers and the soil arching effect, the position of application point of the resultant active earth pressure by the proposed formulation is higher than that of Coulomb’s solution. The wall is rougher, and the resultant pressure will be smaller. The application point distance from the bottom of the wall will increase. Finally, an experiment was conducted to verify the distribution of the active earth pressure for finite soil against rigid retaining wall, and the research results agree well with those of the experimented observations.