Influence of Soil Properties and Composition, and Applied Hydraulic Pressures on Sample Quality of Pusan Clays

Obtaining good quality samples from soft marine clay deposits is a challenge and it is being seen that the sample disturbance is inevitable even though lot of research has suggested using more sophisticated samplers, sampling methods, and special care being taken while handling and transportation of the samples. Hence, author doubt that apart from the above, there could also be other parameters playing critical role on the sample quality. Therefore, in the current study, sampling tube geometry is maintained same, especially angle of cutting edge and area ratio which are found to be key influencing factors and hence its impact on the current study is ignored. In the current study in order to assess the other contributing factors behind the additional sample disturbance, a special attention is given to find out other possible parameters that could also influence the sample quality. As a result of this study, it is found that the soil properties such as; silt and sand content in the soil, clay fraction, hydraulic pressure applied to penetrate the sampler, rigidity index of the soil, initial void ratio, plasticity index, and unit weight of the soil also contribute to sample disturbance. Since these properties, except hydraulic pressure, are soil inherent properties, there is always a certain minimum degree of sample disturbance associated with these soil inherent properties depending on the magnitude of these parameters. Unfortunately, the soil properties cannot be changed and thus a minimum sample disturbance is inevitable.