三维弹性拉索风雨振研究

发布时间：2018-04-24 11:59

本文选题：斜拉索 + 三维弹性　；参考：《长安大学》2015年硕士论文

【摘要】：斜拉桥造型优美,经济适用,是大跨度桥梁首选桥型。拉索是斜拉桥最为重要的受力构件,因其具有较小的质量和阻尼,在风,雨及桥面等共同作用下极易激发振动,产生如尾流驰振,风雨激振,参数共振,涡激共振等。鉴于振动可能引起的拉索疲劳破坏及影响桥梁运营安全等问题,拉索振动机理及抑振措施研究已逐渐成为一个具有重要意义的课题。本文归纳斜拉索风雨振理论,开展了三维弹性拉索的风洞试验,并提出了基于三维弹性节段模型的计算方法,给出了拉索运动方程,静力构型,雨线方程及气动力方程。利用CFD技术,对附加人工雨线拉索的气动力系数进行计算,得出不同风向角及不同雨线初始位置下拉索气动力系数。通过高次多项式拟合出关于气动力系数与初始位置角度的函数,得到气动力半经验公式。采用有限元分析软件ANSYS建立模型,对斜拉索进行风雨激励下的时程分析,分别计算出不同风速,雨线初始振幅,雨线初始位置及风向角等影响下拉索响应情况。定义了最佳阻尼比,通过反馈机制得出拉索在风雨激励下的最佳阻尼比。对相同激励作用下的同一拉索进行风洞试验,对比同工况下试验结果与计算结果的差异,得出相关结论。
[Abstract]:The cable-stayed bridge is the most important bridge type for long-span bridges. The cable is the most important member of the long-span bridge. Because of its small mass and damping, the cable is very easy to excite vibration under the common action of wind, rain and bridge. It produces such as tail flow, wind and rain vibration, parameter resonance, vortex excited resonance, etc. The study of cable vibration mechanism and vibration suppression measures has gradually become an important topic. This paper summarizes the theory of wind and rain vibration of cable cable, carries out the wind tunnel test of three-dimensional elastic cable, and puts forward a calculation method based on the three-dimensional elastic segment model, and gives the cable movement. Equation, static configuration, rain line equation and aerodynamic equation. By using CFD technology, the aerodynamic coefficients of additional artificial rain line cables are calculated, and the aerodynamic coefficients of the cable are obtained at different wind direction angles and different rain lines in the initial position. The model is established by using the finite element analysis software ANSYS. The time history analysis of the cable under wind and rain is established. The response of the cables under the influence of different wind speed, the initial amplitude of rain line, the initial position of the rain line and the angle of the wind direction are calculated respectively. The optimum damping ratio is defined. The optimum damping ratio is defined, and the optimum of the cable under the wind and rain excitation is obtained. The wind tunnel test of the same cable under the same excitation is carried out. The difference between the test results and the calculation results under the same working conditions is compared, and the relevant conclusions are drawn.

【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U441.3;U448.27

【参考文献】