Liquefaction of iron ore fines in maritime transport: advances, challenges and safety perspectives

Liquefaction of iron ore fines remains a major safety concern in maritime transport and has contributed to multiple bulk carrier casualties over the past two decades. This review synthesizes advances published between 2019 and 2025, with a focus on the mechanisms, physicomechanical properties, and environmental conditions that govern liquefaction susceptibility. Key factors include mineralogy, particle size distribution, void ratio, friction angles, undrained shear strength, and cyclic ship motion. Evidence from documented incidents highlights persistent vulnerabilities associated with excessive moisture, inadequate sampling, and uneven enforcement of the International Maritime Solid Bulk Cargoes (IMSBC) Code. The review also examines the Transportable Moisture Limit (TML), Indicative Liquefaction Potential (IPL), and critical incident reports to identify systemic weaknesses. Mitigation strategies, including stricter regulatory enforcement, real-time onboard monitoring, and enhanced crew training—are critically evaluated. Research gaps are identified in four domains: constitutive modeling (CASM, NorSand), development of sensors for real-time TML assessment, comparative studies across deposits, and the influence of climate change on cargo stability. Overall, the findings emphasize the urgent need for interdisciplinary approaches that integrate regulation, monitoring, and advanced geotechnical modeling to reduce liquefaction risks and enhance the safety of global maritime trade.