Reliability-based optimisation design of offshore wind turbine support structures based on active ensemble of surrogates

As offshore wind turbines (OWTs) develop toward larger sizes and deeper waters, their support structures' performance directly affects turbine safety, reliability, service life, and economic viability. Subjected to complex wind, wave, and current loads during long-term service, these structures pose great challenges to failure mode diagnosis, reliability analysis, and optimisation design. To address this, this study proposes a novel reliability optimisation design method for OWT support structures based on a multi-model adaptive ensemble surrogate approach. The method involves establishing the surrogate model, conducting failure assessment considering multiple damage modes, solving the optimisation framework via a decoupled strategy, and validating through a real OWT support structures case study, which confirms its effectiveness and advancement.