Load-factor stability analysis of embankments on saturated soil deposits

A continuum-based finite-element methodology is established for quantifying the stability of earthen embankments built on saturated soil deposits. Wit hin the methodology the soil is treated as a fluid-solid porous medium, in which the soil skeleton's constitutive behavior is modeled using a smooth e lastoplastic cap model that features continuous coupling between deviatoric and volumetric plasticity. In the stability analysis procedure, self-weigh t of the embankment soils is monotonically increased at rates characteristi c of the embankment construction time, until instability mechanisms develop . The transient effects of excess pore pressures and their impact on soil s trength are explicitly modeled, allowing for computation of embankment safe ty factors against instability as a function of construction rate. Details on the proposed method are presented and discussed, including (1) how the c onstruction rate of an embankment can be modeled; (2) how load-based safety factors can differ from resistance-based safety factors: and (3) solved ex ample problems corresponding to a case history of an embankment failure.