Scenario-Based Assessment of Ice-Breaking Cones for a 15 MW Monopile Offshore Wind Turbine in the Bohai Sea

As offshore wind power expands into ice-prone regions such as the Bohai Sea, the applicability of ice-breaking cones (IBCs) to large monopile-supported wind turbines has become an important engineering issue. This study compares the ice-induced vibration responses of a 15 MW monopile offshore wind turbine with and without an IBC under representative Bohai Sea ice and environmental conditions. Rather than enforcing identical ice-failure mechanisms across the two configurations, the comparison is carried out under the representative adverse ice-load scenarios relevant to each structural form. The results indicate that the static ice-load reduction effect of the IBC is strongly dependent on ice thickness; under thick-ice conditions, the extreme static ice force may even exceed that of the structure without an IBC. Dynamic analyses show that, for large and relatively flexible structures, the periodic ice-breaking process induced by the IBC may produce a narrow-band excitation with a dominant frequency close to the low-order natural frequencies of the turbine, which may lead to resonance-sensitive responses under certain extreme conditions. Under typical combined wind–ice conditions in the Bohai Sea, wind loading dominates the structural response in this range, and the difference between the two configurations is therefore limited. These results suggest that, under the present assumptions and loading conditions, the benefit of installing an IBC on a large monopile offshore wind turbine in the Bohai Sea is limited. This study provides a scenario-based assessment for Bohai Sea ice-resistant design rather than a universal conclusion on the necessity of IBCs in all ice-prone regions.