Numerical Evaluation of Passive Earth-Pressure Coefficients under the Effect of Surcharge Loading

Abstract

A numerical protocol was developed for the evaluation of the passive earth-pressure coefficients (Kpq) for the case of an inclined rigid wall retaining an inclined cohesionless backfill loaded with a uniform surcharge. The shape of the proposed failure surface is assumed to be a complete log-spiral. The methodology developed herein uses Kötter’s equation, which enables the computation of soil reactive pressure distribution and the resultant soil reaction on the failure surface. Furthermore, all three limit-equilibrium conditions are effectively utilized to identify the unique failure surface for the given parameters, viz, soil frictional angle (ϕ), wall frictional angle (δ), wall inclination angle (λ), and sloping backfill angle (i). Design tables are also presented for several combinations of ϕ, δ, λ, and i. For validation, the Kpq values obtained are compared with those reported by several other researchers and are found to be in good agreement with most of the available theoretical solutions.