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Challenges in obtaining high quality samples of sensitive low-plasticity clay in an effective manner have been overcome by the development of the mini-block sampler. The starting point for the development of the new sampler was the Sherbrooke block sampler that was first introduced in Canada in 1979. Although the Sherbrooke block sampler can produce high quality samples, its use, particularly in industrial projects, has been limited due to the perceived high costs, practical difficulties, and the time required. This paper outlines details of the development and design of the mini-block sampler together with developed techniques for protection and transportation of the samples and preparation of specimens for laboratory testing. The sampler has been used successfully at five Norwegian clay sites. For two of the sites comparative Sherbrooke samples were available and it is shown that the quality of the mini-block samples is very high and is at least as good as that of the Sherbrooke samples. The work also demonstrates that rigging, preparation, and sampling with the mini-block sampler is fast, practical and is not labour intensive. Furthermore the resulting samples are easy to transport and handle, but still provide sufficient material for extensive laboratory testing. [ABSTRACT FROM AUTHOR]

Probabilistic risk assessments are increasingly being considered the most appropriate framework for engineers to systematically base decisions on hazard mitigation issues. This paper aims to show the advantages of a quantitative risk assessment by application to a historical case study. The generalized integrated risk assessment framework has been applied retrospectively to a submarine landslide that occurred in 1996 near the village of Finneidfjord in northern Norway. Over 1 million cubic metres of predominantly quick clay was displaced. Even though it was triggered underwater on the embankment of the Sørfjord, the retrogressive nature of the slide resulted in it encroaching 100–150 m inland. The triggering mechanism is believed to have been the placement of fill, from a nearby tunnelling project, on the foreshore of the embankment. This paper is a retrospective quantitative evaluation of the risk to the neighbouring houses, the persons in those houses, and the persons in open spaces caused by the placement of increasing levels of embankment fill. A probabilistic approach, making use of second-moment modelling and first-order second-moment approximation is adopted. It aims to demonstrate the advantages of this type of risk assessment in understanding complex and integrated hazards, particularly those in populated environments. [ABSTRACT FROM AUTHOR]

This paper presents 9 years of measured pore pressures from eight piezometers installed in a marine clay slope in southeast Norway and the results of a two-dimensional finite element (FE) analysis performed to evaluate infiltration effects on groundwater flow and pore-pressure response. The assumed time-varying boundary flux record used in the analysis to simulate infiltration considers the effects of temperature, snow depth, land-use practices, and soil hydraulic conductivity. The pore-pressure records and analyses show that: (i) the maximum pore pressure reached is nearly the same each year; (ii) this maximum corresponds to a groundwater surface at or near the ground surface; (iii) the two-dimensional groundwater model used for the analysis is adequate for understanding of factors affecting infiltration, seepage patterns, and pore-pressure variations; and (iv) it is difficult to precisely model all aspects of the observed pore-pressure variations. [ABSTRACT FROM AUTHOR]