Mapping of quick clay using sounding methods and resistivity in the Gota River valley

For a long time, the predominant method for detection of quick clay in Sweden has been to take undisturbed samples and to perform fall-cone tests on the clay in its undisturbed and remoulded state. In connection with a large stability investigation covering both sides of the Gota River, from the lake Vanern to the city of Gothenburg, the usefulness of CPTu and static pressure sounding for mapping of quick clay was studied. Evaluation of the correlation between the slope of the penetration force and the presence of quick clay was done within two areas of this investigation. In addition, a separate study was carried out with the purpose to investigate whether surface resistivity measurements together with sounding, using a CPTu-R with measurement of the total penetration force, in combination with fallcone tests and chemical analyses in the laboratory could give a more complete picture of the presence of quick clay