Embankment Design Method Combining Limit-State Approach with Stress-Path Application

Abstract

A rational design method for embankments on soft soils that takes care of both bearing capacity and stability mechanisms is proposed in this paper. Two types of embankment-construction techniques are used on soft soils: a single-stage construction technique for quickly constructing relatively low-height embankments and a staged-construction technique for constructing high embankments. In this paper, a limit-equilibrium approach is used to estimate the critical slip-surface depth that is assumed to be the bottom line of a possible collapse mechanism under undrained loading conditions corresponding to single-stage construction. In contrast, to design a stage-constructed embankment on soft soils, both undrained and drained conditions must be taken into account. The proposed method can address this behavior and therefore is applicable to embankments constructed in either a single stage or multiple stages. The staged-construction technique, however, necessitates adding the tool of stress-path application to the method to consider both undrained and drained behaviors. This is a property that is not found in limit-state approaches, and it gives the proposed method the capacity to follow and interpret changing stress–strain states and their influence on mobilized strength states.