The Dutch and German governments are providing extensive results of geophysical and geotechnical studies prior to opening the tender phase for development of a new offshore windfarm site. This approach implies a pre-development phase without a defined windfarm layout in terms of turbine locations and inter-array cables. The pre-development approach aims at improving sustainability, including reduction of cost of electricity per kWh. This paper summarises guidance on selection of characteristic values for conceptual geotechnical design of monopiles, prepared as part of the pre-development phase for the Hollandse Kust (noord) wind farm zone, offshore Netherlands. The Dutch government included this guidance in a publicdomain information package provided to tenderers for the design, construction and operation of the wind farm. This paper focuses on challenges for integration and adaptation of multiple sets of derived values to values of geotechnical parameters that are representative for in-situ conditions in mostly sandy soils. The derived values typically cover values obtained from CPT-based correlations and values obtained from interpretation of laboratory results on reconstituted test specimens. The integration and adaptation included considerations for geological setting and applicability of in-situ and laboratory test methods.
J. Peuchen, K. Kaltekis, M. Klein, M. Murali, F. C. W. van Erp and M. A. Hicks
Keywords: wind farm, ground model, geotechnical parameters
Publisher: DFI