中文摘要：

利用有限元软件ANSYS,以密平线改建工程中的一个塔架为研究对象,建立了空间有限元模型,对其进行模态分析得到前10阶自振频率和振型,并分析振型特点,然后采用时程分析法研究输电塔在3种不同地震波作用下的地震响应.分析结果表明,地震作用下铁塔支座反力和反弯矩较静荷载作用下有大幅增长,并且不同类型地震波的加速度响应幅值差别很大,说明弄清楚建筑结构所处场地的类别是设计的关键因素,设计时地震作用对基础的影响不可忽略;塔头控制结点位移符合抗震规范的要求,为进一步控制研究提供了理论基础.

英文摘要：

By using the finite element analysis software of ANSYS and by taking one tower in Minping transfor- mation line as the background of the research, a spatial finite element model is established. By means of mo- dal analysis, the first ten natural frequency and vibration modes are obtained and modal characteristics are summarized. The response difference among three dimensional seismic waves is analyzed by a time-history a- nalysis method. The analysis results show that the support pressure and moment of a tower under an earth- quake action have a larger growth than that of the tower under a weight action. What is more, the difference of different types of seismic wave amplitudes of acceleration responses is very large. The conclusion shows that it is a key factor for the design to make clear the type of site soil on which the structure is located. In a word, the influence of the seismic action on the foundation cannot be ignored. The displacement of a tower head node conforms to the requirements of the aseismic code. The conclusion provides a theoretical basis for the further control research.