The conventional Mononobe–Okabe method is widely used in practice, but is only applicable for calculating total seismic earth pressure of cohesionless soil, not for solving earth pressure distribution. Based on limit equilibrium theory, the backfill is considered to be an ideal elastic–plastic material that obeys the Mohr–Coulomb yield criterion, and a family of slip-lines in the plastic zone is assumed to be a group of straight lines, i.e., planar slip surfaces. Influencing factors including inclination of wall, slope angle of backfill, cohesion and friction angle of soil, adhesion and friction angle between wall and soil, uniform surcharge, and horizontal and vertical seismic coefficients are considered. A more reasonable plastic soil wedge analysis model is established to solve the seismic passive earth pressure on retaining walls, the soil reaction on slip surfaces, and their distributions by using the limit equilibrium method. The geometric and mechanical similarity principle is first proposed by dimensionless analysis. The results show that the total seismic passive earth pressure increases with the algebraic value of the horizontal seismic coefficient, and that it decreases as the algebraic value of the vertical seismic coefficient increases. The present analytical solution is identical to the results in existing literature, and the Mononobe–Okabe method is a special case of this solution.
Behavior of a Braced Excavation in Soft Clay and the Undrained Shear Strength for Passive Earth Pressure
