Geotechnical Site Investigation at the Rentel Offshore Wind Farm

G-tec Offshore SA, on the instruction of Rentel NV, has carried out a geotechnical site investigation at the proposed Rentel Offshore Wind Farm concession area located in the North Sea, approximately 32 km west of Zeebrugge, Belgium.

The purpose of the Rentel Geotech II Campaign geotechnical site investigation was to collect sufficient geological and geotechnical data to:

• Characterise the site;
• Identify the nature and assess the geomechanical properties of the different soil layers encountered in the proposed site;
• Investigate and quantify potential geotechnical risks; and
• Facilitate the design and installation of wind turbine generators (WTG) and an offshore high-voltage station (OSS)

The actual scope of work included:

• Deep seabed piezocone penetration tests (SCPT)
• Down-the-hole piezocone penetration tests (DCPT)
• Advanced sampling boreholes, with continuous disturbed and undisturbed sampling
• Seismic logging throughout the soil profile using a P- and S-wave (P-S) suspension probe
• Reduced pressuremeter (RPM) tests
• A basic offshore geotechnical laboratory testing programme, comprising engineering soil description, classification testing, and estimates of vane shear strength and undrained shear strength using pocket vanes and pocket penetrometers, respectively; and
• An extensive onshore geotechnical laboratory testing programme, comprising classification, chemical and electro-chemical, microbiological, compaction, compressibility, total and effective shear strength, and advanced cyclic testing.