Fluctuating wind field and wind-induced vibration response of catenary based on AR model

Based on AR model and the structural characteristics of catenary, the fluctuating wind field of catenary related with time and space was established.The fluctuating wind loads acting on the catenary were calculated by the simulated wind speed time series.A three-dimensional finite element model of catenary was established to calculate the modes, static wind deviations and wind-induced vibration responses of catenary, and the spectrums of the displacement responses were analyzed in details.Analysis result indicates that the fluctuating wind field of catenary can be established by using Davenport wind speed spectrum because the vertical wind speed is lower than the along-wind speed.While the lateral average wind and natural wind with the speed of 30m·s^-1 acting on the catenary, the maximum lateral displacements of mid-span node of contact wire are 109.11mm and 312.49mm, respectively.The lateral displacement of catenary calculated by the average wind load acting on the catenary decreases by 186.40% compared with the value calculated by the fluctuating wind loads.The lateral displacement of catenary is generated as well as the vertical displacement of catenary under natural wind, the first order vertical and lateral frequencies are 0.973 Hz and 1.384 Hz, respectively, and the windinduced responses of catenary exhibit peak resonant vibration in the zone of the two frequencies.Under natural wind with a speed of 30m·s^-1, the stresses of contact wire and support wire caused by the wind loads are about 10.77% and 27.40% of their total stresses, respectively.Therefore, the fluctuating wind loads should be applied to conduct the wind deviation and strength design of catenary.