【摘要】 基于AR模型和接触网结构特性,建立了具有时间和空间相关的接触网脉动风场,由模拟的风速时程获得作用于接触网的风荷载;建立接触网三维有限元模型,研究了其模态、静态风偏和风振响应,并对位移响应进行了频谱分析。分析结果表明:垂向风速相对顺风向风速较小,采用Davenport风速谱可建立接触网脉动风场;接触网在30m·s-1的横向平均风和自然风作用时,接触线跨中节点横向位移的最大值分别为109.11mm和312.49mm,平均风荷载下计算得到的接触线横向位移减小了186.40%;接触网在横向自然风作用时,接触线横向和垂向振动位移同时产生,接触网第1阶垂向和横向振动频率分别为0.973Hz和1.384Hz,在这2阶频率处产生了接触网结构与风荷载的峰值共振;接触网在30m·s-1的自然风作用时,由风荷载引起的应力分别占接触线和承力索总应力的10.77%和27.40%,因此,需采用脉动风荷载进行接触网的风偏和强度设计。更多还原

【Abstract】 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.3tabs,11figs,15refs.更多还原