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A large landslide in Tuve (Gothenburg, Sweden 1977) initiated the development of a model for slope stability analysis taking the deformation-softening of soft sensitive clays into consideration. The model studies triggering agents and five phases in progressive slope failure are identified: (1) in-situ, (2) disturbance, (3) unstable ‘dynamic’, (4) transitory (or permanent) equilibrium, and (5) ‘global’ failure. The clay resistance in these phases may differ widely; mostly due to different rates of loading. Two time dependent failure criteria are defined: (i) the triggering load condition in the disturbance Phase (2), and (ii) the transitory equilibrium in Phase (4), indicating whether minor downhill displacements or a veritable landslide catastrophe will occur. The analysis explains why downhill landslides tend to spread over vast areas of almost horizontal ground further down-slope. The model has been applied to landslides in Scandinavia and Canada. Three case studies are briefly discussed. The model is a finite difference approach, where local downhill deformations caused by normal forces is maintained compatible with deviatory shear deformations above the potential (or the established) failure surface. Software and an easy-to-use spreadsheet are introduced as well as recent developments. See also Video Abstract. Validerad; 2016; Nivå 2; 2016-11-02 (andbra)

In Sweden the bearing capacity of axially loaded floating piles in soft clay is calculated using the undrained shear strength of the clay (often determined by the field vane test). In this study several load tests, compression as well as tension tests, have been made on well-instrumented piles. The results from these tests, in combination with thorough investigations of the field vane test, have led to a well-documented understanding of the behaviour of floating piles in soft clay.In the article, a method is presented that makes it possible to calculate the load–displacement variation in the permissible load range, as well as the bearing capacity. Results from several load tests are presented and predictions are compared with performance. Keywords: soft clay, time dependence, floating piles, bearing capacity, load tests, method of calculation, case histories.