Norwegian research into the properties of quick clay—a review

The ultra-sensitive type of clay called quick clay has caused severe landslides in Scandinavia and on the east and west coast of Canada. Slides of this type were the mentioned in literature in the fourteenth century. Quick-clay properties were described in 1901. Later geologists at the Norwegian Geological Survey, the Norwegian Highway Laboratory and the Norwegian Geotechnical Institute carried out research on this material. The present opinion is that the peculiar properties are based upon colloidal-chemical phenomena. According to this the clays deposited and consolidated in a flocculated state. Later chemical changes increased the double layer potential, either by leaching of electrolyte or by addition of suitable anions. The flocculated structure remains, unstable though, until mechanical disturbances cause a breakdown. Thus the clay is transformed into a dispersed state.