The rapid expansion of offshore wind energy demands quieter, more sustainable foundation installation methods. Traditional pile may generate harmful underwater noise, prompting the need for alternatives. This study investigates the feasibility of a “pushed-in” pile installation technique using a cluster of four hydraulically jacked piles, offering a silent solution for offshore wind turbine foundations. Centrifuge testing was conducted to assess the influence of installation sequence, pile diameter, and spacing on method efficiency. Results show that the pushed-in method enables pile embedment depths up to four times greater than those achieved under static weight alone, with reaction forces nearly double the tool weight due to mobilised tensile resistance. Efficiency improves with smaller pile diameters and wider spacing, while control strategies that minimise reaction pile displacement and optimise force distribution significantly enhance performance. Among three control methods tested, the third – featuring a final force equalisation – yielded the highest efficiency and depth. These findings inform the design of full-scale installation tools and suggest that clusters of smaller piles may offer superior performance. These results can inform future work such as the development of a predictive method base on CPT data to predict refusal and resistance of the cluster.
Cerfontaine et al. (Sun,) studied this question.