【摘要】 采用有限元离散大型输电塔，并应用 Ｐｒｉｅｓｔｌｅｙ 的演变谱理论分析了大型输电塔在非平稳随机地震激励作用下的响应演变谱和时变协方差，考虑了不同场地土对响应演变谱和时变协方差的影响情况，得出了一些有益的结论。更多还原

【Abstract】 An efficient analysis of the non stationary random seismic response of large transmission towersis presented. The structure is discretized by the finite element method for getting the time invariant mass and stiffness matrices. In the analysis,it is assumed that the structuce possess classical damping properties and the normal mode method is applied. Based on Priestleys evolutionary spectrum theory, the evolutionary spectra and the time variant cross correlation function of the response for the structure subjected to non stationary random seismic excitation are investigated. The non stationary random seismic excitation is represented by the product of a stationary random process with zero mean and a deterministic envelope function of time. The numerical examples show that the non stationary response of structure is affected significantly by the soil types and different parameters of modulation function.更多还原