基于风场模拟的接触网b值动态响应分析

接触网线索受风振动会造成b值变化,为了将风荷载引起的变化量剔除,对随机风场作用下的接触网进行仿真研究。利用ANSYS软件建立全补偿简单链形悬挂接触网模型;采用谐波叠加法模拟得到随机风场;分析b值风致变化的机理,仿真完成了接触网模型在不同随机风荷载作用下的动态响应分析。研究结果表明:接触网b值风致变化是线索受风偏移导致的结果,横向偏移起主要作用;脉动风场作用下接触网各跨会随机产生不同大小的补偿位移,随着风速提升补偿位移振幅相应变大且变化率呈增大趋势;对于半个锚段12跨接触网,当风速达到41m/s时,补偿位移振幅为60.61 mm,接近棘轮补偿装置断线b值变化量,说明识别断线事故时应考虑风振的影响。

Analysis of Dynamic Response of Catenary b Value Based on Wind Field Simulation

The b value will be changed when the wind induces vibration of the catenary wire. In order to eliminate the variation caused by wind load,simulation of the catenary under the action of stochastic wind field is carried out. Firstly,ANSYS software is used to establish the finite element model for the completely-compensated simple catenary suspension,and then weighted amplitude wave superposition method is employed to simulate the stochastic wind field. Finally,the mechanism of the change of b value caused by wind load is analyzed and the analysis of dynamic response of the catenary under different stochastic wind load is completed by simulation. Research results show that the change of catenary b value is caused by the deviation of the wires due to wind and the lateral migration plays a major role; the compensation displacement of different spans could be generated randomly under the action of fluctuating wind field; with the increase of wind speed,the amplitude of compensation displacement becomes larger and the change rate also increases; when the wind speed reaches 41 m / s,the amplitude of compensation displacement of the half anchor section with 12 spans adds up to 60. 61 mm,which is close to the broken wire variation value of the ratchet wheel compensation device,indicating that the influence of wind induced vibration should be considered when identifying the wire breaking accident.