Characterisation of quick clay at Dragvoll, Trondheim, Norway

Abstract

A detailed characterisation of the quick clay underlying the NTNU research site at Dragvoll, Trondheim is presented. The objective of the work is to provide guidance on quick clay parameters to engineers and researchers working with similar clays in Scandinavia and North America. Dragvoll clay is characterised by its high sensitivity and is quick at relatively shallow depth. The material exhibits low undrained shear strength and high compressibility except over a shallow overconsolidated zone. Its properties are similar to other quick clays in the area and are consistent with well know correlations for Norwegian clays. A combination of simple index tests such as water content and Atterberg limits and CPTU testing proved very useful in characterising the material. The material is very sensitive to sampling and laboratory handling. Results of standard and non standard tests, such as piezoball testing, are presented.