Comparison of Self Weight Penetration Prediction Methods for Large Diameter Monopiles in North Sea Soils

摘要

A significant number of large diameter monopiles (>6 m diameter) have been installed as foundations forrnoffshore wind turbine generators (WTG) across Northern European waters over the past decade, where thernself-weight penetration (SWP) during the installation process was recorded. The prediction of the SWP forrnoffshore foundations, such as piles and skirted foundations, is an important installation design task. Thernprediction of the SWP is subject to great uncertainty, resulting in a large range between lower and upperrnbound SWP predictions.rnThe methods available to predict the SWP range from simple empirical methods that derive thernpenetration resistance from cone penetration test (CPT) measurements using skirt and tip resistancerncoefficients to more advanced methods, based on bearing capacity theory requiring soil strength parametersrnas input. For the empirical methods, the prediction accuracy is directly dependent on the data used tornestablish suitable resistance coefficients. Investigating different soil conditions and foundation dimensionsrn(scale effects), therefore, extends and improves the applicability of the empirical SWP prediction methods.rnThis paper will use a portion of the recorded SWP data to benchmark existing SWP prediction methods andrnto establish improved resistance coefficients for the empirical method using a Monte Carlo type approach.