GeoSea executed a soil investigation campaign for Teesside Wind Farm Ltd. The client required 100mm diameter high quality samples from the boulder clays and bedrock allowing the engineer to assess the drivability of the planned mono-piles. HPD testing was necessary in order to determine the strength and stiffness properties of soils and rocks at different bed rock levels. The works were performed in very challenging weather conditions.
GeoSea used its steady jack up platform Vagant to cope with the sea conditions. Sampling and CPTU were performed simultaneously using two rigs installed above two moonpools. In total 6 CPTU’s and 6 boreholes including several HPD tests were executed. Sampling was carried out using push sampling techniques, core sampling techniques and sonic sampling techniques. In stiff cohesive clays and chalk GeoborS triple wireline core drilling was used as sampling method, providing 102mm diameter samples. The sonic sampling method was used as sampling technique in non-cohesive materials (e.g. gravel and loose sand) providing high sample recovery rates.