Geotechnical Risk in Offshore Wind: A Critical Review of Pile Running during Monopile Installation

• This review systematically collates 22 global pile running cases of offshore monopiles, clarifying the correlation between pile types, three typical unfavorable geological conditions and pile running occurrence, and identifying the core mechanism as sudden loss of soil shaft and tip resistance. • It comprehensively evaluates the latest progress of pile running research from dynamic resistance evolution, post-running bearing capacity assessment, zone prediction and mitigation measures, and compares the advantages and limitations of empirical, energy-based and deep learning methods. • The study points out the key limitations of current research and proposes targeted future directions including digital twin sensing, AI-driven active risk control and design code revision, providing a comprehensive reference for offshore wind pile running risk management. Offshore wind energy plays a pivotal role in the global transition towards a sustainable energy future. The monopile foundation has become the predominant solution for supporting offshore wind turbines in shallow to intermediate water depths. However, the installation of these large-diameter monopiles poses significant geotechnical risks, among which “pile running” (i.e., a sudden, uncontrolled penetration event during driving) is a critical hazard. This phenomenon can lead to severe consequences, including structural damage to the pile and hammer, posing threats to project safety, cost, and schedule. This review systematically synthesizes global research on pile running in marine geotechnical engineering. It begins by outlining the application of monopile foundations and cataloging 24 documented case histories of pile running across diverse geological settings. The core analysis delves into the fundamental causes, underlying mechanisms, and evolving mechanical characteristics of pile running, with a focused examination of the rapid changes in shaft friction and tip resistance that govern the event. Subsequently, prevailing predictive models and calculation methodologies for assessing pile running susceptibility are critically compared and evaluated. Furthermore, the review addresses the evaluation of post-running pile capacity and summarizes current mitigation strategies and identifies future research priorities. By integrating insights across these domains, this review aims to provide a comprehensive reference that enhances the prediction accuracy and risk control of pile running. This effort contributes directly to ensuring the safer installation and long-term reliability of monopile foundations, thereby supporting the sustainable and cost-effective expansion of offshore wind energy.