Vibratory Extraction of Offshore monoPiles

The offshore wind industry is expanding rapidly, with over 100 GW of installed capacity expected in the EU by 2050. Decommissioning of monopile foundations, however, remains an unsolved challenge. Early attempts cut monopiles at the seabed, discarding millions of tons of recyclable steel and preventing reuse of the seabed. New regulations increasingly require full removal, yet static pull-out demands enormous forces: while a few vessels can manage early-generation monopiles, none worldwide can extract XXL monopiles. This creates an urgent need for new extraction methods that are both feasible and sustainable.VExOP (Vibratory Extraction of Offshore Piles) will tackle this by investigating how controlled vibrations of monopiles can fluidise sand and reduce soil–pile friction, enabling extraction. Unlike liquefaction, vibration-induced fluidisation also occurs in dry granular media, making it a distinct and poorly explored mechanism. While vibratory driving is proven onshore for small piles, its offshore use for XXL monopiles is nascent, and its application to removal remains largely unexplored, with limited studies and no predictive framework.The project will combine small-scale modelling and high-resolution imaging with centrifuge experiments and Discrete Element Method (DEM) simulations to reveal the mechanisms of vibration-induced fluidisation. Results will be synthesised into a simplified engineering model and implemented in an open-access web app to deliver practical tools for industry.Hosted at the University of Southampton, the fellowship will provide training in DEM, digital image correlation, and open science, while strengthening leadership and interdisciplinary skills. VExOP will foster independence, broaden collaborations, and enhance career prospects. By pioneering vibro-extraction, it will lay the foundations for sustainable monopile decommissioning, promoting circularity, reducing costs, and supporting Europe’s transition to net zero.