A new method of finding the critical slip surface in slope stability analysis is developed in this paper, based on the limit equilibrium technique with added stress acceptability criterion. The stress acceptability criterion is based on the limited strength of soil. The slip surface is developed in terms of the critical acceleration. The procedure uses stress acceptability as a prerequisite to derive a system of non-linear equations to determine the slip surface slice by slice upwards; no prior assumption of the shape of the surface is needed. This surface simultaneously satisfies the kinematical acceptability criterion. The whole procedure includes both homogeneous and non-homogeneous slopes. In terms of the minimum factor of safety, the obtained critical slip surfaces compare well with those obtained through methods based on optimisation techniques. In addition, the solution provides information on the critical acceleration and the kinematically acceptable interslice boundaries for the analysis of seismic displacements of slopes using a multi-block sliding model.

Describes two low‐order shell elements, one (quadrilateral) with 16 degrees‐of‐freedom; twelve translations and four rotations and another (triangular) with 12 degrees‐of‐freedom; nine translations and three rotations. The elements are formulated in a geometrically non‐linear manner and large strains, which may be hyper‐elastic or elasto‐plastic, are also considered. Hills yield criterion with a Lankford constant for the special case of transversely isotropic problem is introduced into the large‐strain formulations. To illustrate its application, the hydrostatic bulging of rectangular diaphragms with different aspect ratios is analysed and the obtained results are compared with the experimental ones. The elements have advantageous nodal configuration that makes them particularly suitable for analysing structures with junctions. Such a problem is an initially square steel box loaded with internal pressure. This problem is analysed and comparisons are made with experimental results.

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To determine the critical slip surface in slope analysis, a new procedure has been proposed, based on limit equilibrium method and stress acceptability criteria. This paper uses finite element analysis as an independent tool to validate the new procedure for both homogeneous and non-homogeneous slopes. Good agreement is found between the new procedure and finite element analysis, in terms of the critical acceleration, the critical slip surface and normal and shear stress distribution on the slip surface, in both homogeneous slopes and non-homogeneous slopes. However, when non-associated flow rules are adopted in finite element analysis and the corresponding degree of non-normality is high, some differences are noticed. The reason for this difference is explained.