Geotechnical Classification of Søvind Marl

This article deals with the geotechnical classification properties of a Danish Eocene clay known as Søvind Marl. A large development is happening on locations where the soil consists of different varieties Danish Eocene clays. This gives a need for a better understanding of the properties and behavior of the clay. The geotechnical properties of the clay are very unique, due to the very high plasticity index of the soil, which is significantly higher than any other known clay. The Søvind Marl is a Tertiary deposit from the Eocene period, deposited under environmental circumstances very similar to the environment under which London Clay was deposited, however the properties do not resembles that of London Clay. The liquid limits of the Søvind Marl are very high, with values between 126% and 331%, and plasticity limit consistently around 50%. Besides the plasticity of the Søvind Marl other properties like; natural water content, lime content, vane strength and the pH-value and chloride content of the pore water is described. The composition of clay minerals has a big influence on the behavior of clay. Søvind Marl has a high content of clay minerals; between 75% and 95% has a grain diameter of less than 2 μm, and the remaining material mainly consists of lime. There is a large variety of different clay minerals in the Søvind Marl, and the composition changes through the depth and the properties of the clay therefor also changes significantly through the depths.