【摘要】 将非平稳地面运动的加速度表示为零均值的平稳随机函数乘以调制函数的形式,借助于虚拟激励法,解决了计算量与精度的矛盾,计算了大跨空间索结构的随机地震响应,即时变加速度功率谱和时变位移方差,比较分析了多点和一致2种输入方法下索结构非平稳响应的差异及多点输入下结构平稳和非平稳响应的差异,并且分析了视波速、结构跨度和阻尼比等因素的影响。通过分析可以看出虚拟激励法对于分析大跨度空间索结构的非平稳随机地震响应是非常适合的,而且是高效的。更多还原

【Abstract】 The ground motion acceleration is expressed as the product of the modulation function and stationary random function with zero mean value,the time-dependant power spectrum and the time-dependant displacements response variance of joints are accurately computed with the pseudo excitation method with high precision for long-span space cable structures,and the difference and change order of the structure response are studied generally under multiple support excitation and simple support excitation.Some important conclusions about the effect of apparent velocity,the span and damping ratio on the seismic response are gained.The calculation shows that the pseudo excitation method is efficient and precise in the seismic response analysis of the complicate structures,such as long-span space lattice structures,under multiple support excitation.更多还原