Nataf-based probabilistic buffeting prediction of overhead transmission lines under multi-dimensional turbulent wind excitation

The overhead transmission line (OTL) is a complex nonlinear system susceptible to turbulence-induced buffeting. Classical one-dimensional buffeting analysis overlooks potential vertical turbulence. Additionally, the turbulence parameters associated with stochastic wind fields are simply assumed to be deterministic. Such simplified schemes might cause severe misestimation of extreme responses. Therefore, this paper presents a Nataf-based probabilistic buffeting prediction framework of OTLs under multi-dimensional turbulent wind. Initially, a two-dimensional influence line method is introduced to replace the time-consuming nonlinear finite element analysis (NFEA). Subsequently, Nataf transformation is employed to generate turbulence parameter samples, effectively preserving the marginal probability distribution and correlation structure. Then, the three-dimensional wind speeds are simultaneously synthesized, and the impact of turbulence parameter uncertainty on wind field characteristics is investigated. Next, the time-frequency buffeting responses are analytically estimated, and a quantile-based approach is proposed to quantify the uncertainty of extreme buffeting responses. Finally, the stochastic sensitivity analyses are performed to determine the relative sensitivity of various responses to each turbulence parameter. The results demonstrate that the two-dimensional influence line method exhibits significant efficiency advantages; All deterministic extreme responses are less than the 0.5 quantile of uncertain results; The top three turbulence parameters in sensitivity ranking are identical under different conditions.