Dimension-reduced probabilistic approach of 3-D wind field for wind-induced response analysis of transmission tower

Abstract

Reasonable description and simulation of the stochastic wind field on probabilistic level lays a significant foundation for the elaborative dynamic response analysis and reliability assessment of complex wind-induced structures. To this end, a dimension-reduced double proper orthogonal decomposition (DR-DPOD) approach for simulating 3-D stochastic wind velocity field is proposed. The theoretical context of DPOD of 3-D wind field is firstly deduced. Then the random function expression, which contains just 3 elementary random variables, of orthogonal random variables in DPOD formula is proposed to circumvent the challenges that the conventional simulation approaches related to the Monte Carlo sampling (MCS) confronted. For the sake of enhancing the efficiency of numerical calculation, the simulation procedure involving the fast Fourier transformation (FFT) is subsequently introduced. Using the proposed approach, a probabilistic 3-D stochastic wind velocity field acting on a power transmission tower is simulated, followed by the non-linear wind-induced dynamic analysis and wind-resistant reliability assessment of the employed transmission tower being carried out by combining the proposed approach and the probability density evolution method (PDEM). The efficiency and accuracy as well as engineering practicability of the proposed approach are illustrated through the comparisons with the conventional approaches related to MCS. The results of analysis concerning PDEM also reveal that the transverse wind-resistant ability of the transmission tower should be enhanced.