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Stability analysis of retaining walls in seismic areas is generally performed by calculating a safety factor against a possible mechanism of collapse. However, considering that limit conditions usually occur in some time intervals during an earthquake, a more rational approach consists in assessing the performance of the structure in terms of accumulated permanent displacements. In this context, a novel method is proposed in the present study for predicting the earthquake-induced permanent displacements of embedded cantilever retaining walls, such as diaphragm or sheet-pile walls. This method requires solving a simple motion equation of the structure subjected to the soil–structure contact stresses evaluated using a closed-form solution. Specifically, it is assumed that the wall undergoes a rigid rotation around a point located in its embedded portion. Comparisons are presented with both experimental and numerical results documented in published studies. In all cases considered, a satisfactory agreement is found between these results and those provided by the proposed method. In addition, the method accounts for some features of the seismic behaviour of embedded cantilever retaining structures observed during centrifuge tests. Summarising, the method is reliable, simple to use and requires few conventional parameters as input data. Therefore, it is suitable for routine applications. [ABSTRACT FROM AUTHOR]

A simple-to-use analytical solution for radial consolidation with vertical drains under equal strain conditions is presented in this paper. This solution accounts for the effects of soil smear, drain hydraulic resistance, and general time-dependent loading. A number of comparisons with other theoretical methods are shown to assess the accuracy of the proposed solution, both in terms of excess pore-water pressure and degree of consolidation settlement. Moreover, two case histories documented in the literature are analysed to evaluate the main parameters affecting radial consolidation in the presence of vertical drains. Key words: radial consolidation, vertical drains, time-dependent loading, theoretical solution. Une solution analytique, qui est tres simple a employer, est presentee dans cet article pour analyser la consolidation radiale en presence de drains verticaux et en conditions de deformations verticales uniformes. Cette solution permet de tenir compte des effets de l'etalement du sol, de la resistance hydraulique des drains et des charges variables avec le temps de quelque maniere que ce soit. On presente un certain nombre de comparaisons avec d'autres solutions theoriques pour etablir la precision de la procedure proposee, aussi bien en termes de surpression interstitielle qu'en termes de degre de consolidation du tassement. En outre, la solution est utilisee pour analyser les resultats experimentaux de deux cas reels documentes dans la litterature, et pour obtenir des parametres principaux qui influencent la consolidation radiale en presence de drains verticaux. Mots-cles : consolidation radiale, drains verticaux, chargement variable avec le temps, solution theorique., Introduction Vertical drains together with preloading by surcharge embankment are often used for the purpose of accelerating the consolidation of compressible fine-grained soil deposits before construction, by providing a drainage [...]

Abstract: The paper deals with one-dimensional consolidation of saturated clays with variable compressibility and permeability. A formulation is developed to analyse the consolidation of thin clay layers subjected to time-dependent [...]

Abstract: This paper presents an analytical solution for the analysis of one-dimensional consolidation of saturated soil layers subjected to general time-dependent loading. A simple calculation procedure that makes use of [...]

Traditional numerical methods, such as the finite element method or the finite difference method, are generally used to analyze the slope response in the pre-failure and failure stages. The post-failure phase is often ignored due to the unsuitability of these methods for dealing with problems involving large deformations. However, an adequate analysis of this latter stage and a reliable prediction of the landslide kinematics after failure are very useful for minimizing the risk of catastrophic damage. This is generally the case of the landslides triggered by an excess in pore water pressure, which are often characterized by high velocity and long run-out distance. In the present paper, the deformation processes occurring in an ideal slope owing to an increase in pore water pressure are analyzed using the material point method (MPM) that is a numerical technique capable of overcoming the limitations of the above-mentioned traditional methods. In particular, this study is aimed to investigate the influence of the main involved parameters on the development of a slip surface within the slope, and on the kinematics of the consequent landslide. The obtained results show that, among these parameters, the excess water pressure exerts the major influence on the slope response. A simple equation is also proposed for a preliminary evaluation of the run-out distance of the displaced soil mass. [ABSTRACT FROM AUTHOR]