Scouring Analysis and Mitigation Strategies for Scouring on Offshore Jacket Foundations

As offshore jacket foundations gain popularity for their structural advantages, their vulnerability to seabed scouring - localized erosion caused by hydrodynamic forces - presents a significant engineering challenge. Scouring can severely compromise a foundation's bearing capacity, threatening structural integrity and operational safety. This study develops a three-dimensional numerical model using FLOW-3D to comprehensively analyze the effects of scouring on 4-leg jacket foundations under various environmental conditions. The research investigates three primary mitigation strategies: riprap, concrete collars, and a novel geotextile-artificial vegetation (geo+grass) combination. Our findings indicate that scouring depth increases non-linearly with flow velocity and that the combined effects of waves and currents are more destructive than either alone. Crucially, the numerical model successfully simulates the complex vortex shedding and sediment transport patterns responsible for scouring. The geotextile-artificial vegetation system demonstrated the highest effectiveness, reducing scour depth by up to 63% compared to unprotected scenarios. This study provides a validated predictive framework for assessing scour risk and offers a sustainable, highly effective mitigation strategy, contributing valuable insights for the design and long-term management of offshore infrastructure.