Geotechnical and Geological Characterization of a Quick Clay Site at Flotten,Trondheim

Abstract

This work presents the geotechnical and geological characterization of a quick clay site at Flotten which is one of NTNU s research sites in Trondheim, Norway. To characterize the material, number of laboratory tests were carried out in the geotechnical laboratory. These are index tests (such as water content, density measurement, grain size distributions, atterberg limits, salinity, falling cone test and unconfined compression), oedometer and triaxial tests. The deposit in the area is over-consolidated above about 8m and normally consolidated below that depth. Over-consolidated modulus of about, Moc=5Mpa, modulus in normally consolidated range, Mnc=3Mpa, and modulus number, m=18.2, on average. The deposit is composed of a fraction of clay of 50% to 78% and silt 22% to 50% except the top layer,2m to 2.4m, which is a fine sand. An average water content and bulk density of about 45% and 1.79g/cm3 respectively and plasticity index ranged from 9% to 41.57%. The undrained shear strength increases with depth and is about 45kpa to 60kpa. The overall study shows that the property of the material in the area is consistent with correlations for Norwegian clays.