Objective Under the guidance of the "dual carbon" strategy, China's offshore wind power installed capacity continues to grow. Based on the analysis and summary of the design process of a wind turbine jacket foundation at an offshore deepwater site, which is typical for the 2024 offshore wind power competitive allocation, the paper summarizes the dimension optimization strategies of jacket foundation. The explicit, process-oriented and digitalized knowledge of design strategy is conducive to technology precipitation and the development of automated design tools.

Method By analyzing the pilehead configuration of jacket in the pre-pile design, the discrete grouping principle of water depth vs pilehead elevation is determined. The optimum flow of pile diameter under a given footprint is defined by sorting out the relevant design codes of pile foundation bearing capacity and grouting connection design. According to the assembly characteristics of jacket structure, the demension driving parameters were merged, the optimization boundary conditions were identified, and the optimization strategies were formulated.

Result The research shows that the grouping according to the water depth is beneficial to control the number of jacket models. The pile diameter optimization should be carried out before the footprint optimization, according to the sequence of frequency-grouting connection-pile length design. The minimum independent dimension variable set is proposed and the optimization process storage matrix is constructed.

Conclusion When the driving depth of steel piles is restricted, the bearing capacity envelope principle should be adopted, otherwise the sand proportion moment envelope principle should be adopted. Pile diameter optimization is a problem of optimizing the overall steel consumption of grouting legs and steel piles under the restrictions of the overall frequency, grouting axial force & bending moment bearing capacity and axial pile foundation bearing capacity. The cross section optimization of the member should be based on the minimum independent size variable group and be constrained by the configuration requirements. The outer diameter should be optimized first, and the optimization triggering condition, oscillation suppression mechanism and iteration exit condition should be set.