Geotechnical characterization of sediments from the Rockall Bank Slide Complex

• Main Author: van Opdurp, Dylan (author)
• Other Authors: Gavin, Kenneth (mentor), Ngan-Tillard, Dominique (graduation committee), Broere, Wout (graduation committee), Lanzafame, Robert (graduation committee), Delft University of Technology (degree granting institution)
• Format: Master Thesis
• Language: English
• Published: 2020
• Subjects: Rockall Bank; Iceland
• Online Access: http://resolver.tudelft.nl/uuid:b24ad7aa-4eee-4f1f-ad8c-fbdba9df5154

The main reason for this research is the possibility of landslides that could trigger a tsunami together with general interest from the oil and gas industry. The goal of this thesis is to find out what the geotechnical properties are of the 7 different locations at the eastern flank of the Rockall bank which is located to the west of Ireland and to the south of Iceland in the Atlantic Ocean. The possible effects of these properties on slope stability are then discussed. This will be done by geotechnically testing the sediments in a laboratory. All standards used during testing can be seen in chapter 3.1.1. The gravity cores used for this research were found to contain parts of sediment that were quite intact together with other more disturbed parts of sediment. The sediments that were found could be classified as silty SAND, clayey SILTS and silty CLAYS which are calcareous to very higly calcareous,from medium to very high plasticity, low to medium-organic and have extremely low to very low undrained shear strengths. Grain size distribtions were found to be gap-graded and well graded and the the sediments were found to be inactive to normal soil based on the Atterberg limits.Geotechnical properties such as gravimetric water contents are found to range from 0.20 to 1.18, the volumetric water contents range from 0.50 to 0.80, a liquidity index from 0 to 3, specific gravities from 2.72 to 2.79, void ratios from 1 to 3, bulk volumetric weights from 14 kN/m3 to 18 kN/m3, dry volumetric weights from 7 kN/m3 to 13 kN/m3, clay contents from 10% to 60%, a silt content of 15% to 60%, a sand content from 8% to 70%, calcite contents from 17.3% to 57.4%, organic matter contents from 2.6% to 9.0%, liquid limits from 0.40 to 0.82 and plastic limits from 0.23 to 0.49. The undrained shear strength for the original and remoulded sediments from the UU DS tests is found to range from 2 kPa to 8 kPa and from 0 kPa to 4 kPa. The undrained shear strengths from original and remoulded sediments from the fall cone test range from 4 kPa ...