ABSTRACT
Laboratory tests to determine the limits of the liquid and plastic are by far the most widely used index tests and are often adopted to assess the mechanical behaviour of clay. The laboratory investigation results for determining liquid limits using the Fall-cone method and method based on Casagrande-type devices for high-plastic clays were analysed. The density of the soil particles was determined by the pycnometer method by fluid displacement and the pycnometer method by gas displacement. Helium was used as the measurement gas. Significant differences were observed based on the laboratory method used. The range of differences in the geotechnical properties of high plastic clays was 10 to 30 %. The impact of the testing methods on the intrinsic properties of high plastic clays is analyzed in the paper.
