Environmental load data are an essential input for the analysis of offshore wind structures in typhoon-prone marine environments. However, numerical simulations of typhoon waves lack a systematic examination of the specific influence of typhoon trajectories on the spatial evolution of wave fields. In particular, the intricate mechanisms governing wave propagation within wind farm areas remain poorly understood. This present study, drawing upon a real-world case in an offshore wind farm area in the South China Sea, employs the Finite Volume Coastal Ocean Model–Surface Wave Module (FVCOM–SWAVE) wave–current coupling model to assess the joint wind–wave distribution characteristics during 35 typhoon events. The findings reveal that typhoon wave fields exhibit a notable rightward bias. As waves approach the coast, the significant wave height decreases progressively due to wave breaking, friction, refraction, and nonlinear interactions. During the passage of typhoons Prapiroon, Hato, and Mangkhut, the significant wave height distribution in the wind farm area closely correlated with the wind speed distribution. By constructing a joint distribution function of sea wind and wave elements, the joint distribution characteristics of wind speed and significant wave height for different return periods can be obtained, providing important oceanic environmental inputs for the design analysis of offshore wind structures.

The sea ice failure mode and ice force amplitude depend on the structural form at the point of interaction, but the impacts of ice load when interacting with marine engineering structures with additional attachments are not yet clear. This study conducts numerical simulations using the discrete element method to investigate the interaction between sea ice and cable pipes attached to offshore substation structures. Various operating conditions such as ice velocity, ice thickness, and ice attack angle are selected to simulate the interaction between sea ice and such structures, clarifying the variations in the sea ice failure mode and ice force amplitude. The results indicate that crushing failure mainly occurs when sea ice interacts with such structures, and the presence of cable pipes does not alter the sea ice failure mode at the legs of offshore substation structures. The preliminary action of sea ice with cable pipes effectively reduces the ice load on the structure, and the minimum ice force amplitude occurs at an ice attack angle of 90°, with the ice force amplitude increasing with the ice thickness but showing no clear correlation with the ice velocity. The findings of this study provide a reference for the ice-resistant design of offshore substation structures in cold regions.