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The Medusa SDMT is the last-generation, fully automated version of the seismic dilatometer (SDMT). An extensive in situ testing campaign with the Medusa SDMT was carried out in June 2022 in different soil types at four well-known benchmark test sites in Norway, part of the Geo-Test Sites (NGTS) research infrastructure managed by the Norwegian Geotechnical Institute. The experimental campaign was conducted as part of the Transnational Access project – JELLYFISh funded by H2020-GEOLAB. This paper presents a preliminary assessment of significant results obtained by Medusa SDMT at the Onsoy test site, a soft marine clay. The data is compared to available in situ and laboratory data previously published at the Onsøy test site. The results show that the Medusa SDMT data are consistent with traditional (pneumatic) SDMT results. Furthermore, the parameters obtained from the interpretation of Medusa SDMT data, in particular the overconsolidation ratio OCR, the coefficient of earth pressure at rest K0, and the undrained shear strength su agree generally well with the corresponding parameters obtained in past investigations from other in situ and laboratory tests.

High quality sampling of sand and silty sands is extremely challenging. Undisturbed samples of sand can be obtained by means of very expensive and time-consuming techniques such as ground freezing. Given the high costs and expertise required to obtain undisturbed sand samples through ground freezing, piston sampling techniques are usually used in engineering practice. This paper summarises the experiences, technical difficulties, disturbance analyses and issues encountered during sand sampling at the Norwegian Research Site at Øysand using piston sampling and ground freezing technology. Two state-of-the-art piston samplers were used (NGI-Geonor composite piston sampler and Geonor K-200 thin-wall push piston sampler) along with the state-of-the-art Japanese gel push piston sampler. Ground freezing was successfully achieved also both on sands and silty sands at Øysand. Sample disturbance was assessed qualitatively and quantitatively through analysis of micro-computed tomography images. Results from these analyses provide an overview of the strengths and weaknesses of the three piston samplers in comparison with ground freezing, together with recommendations for sampling of sands using piston techniques.

In this article, the authors survey the evolution of the Pratt & Whitney company's assistance program for their employees. Observing that their employees had problems with alcoholism, the personnel development developed a help program for the alcoholics which in the course of the years has also become a help program to the alcoholic's families. The authors summarize the principal problems treated, the program's mode of operation and make a summary evaluation.