超高层钢结构地震反应谱特征分析

为分析超高层建筑楼面地震反应谱特征，计算了国家金融信息大厦超高层钢结构在不同输入地震动下的楼面地震反应谱。从地震系数、动力放大系数、特征周期和动力放大系数谱谱型4个方面对比了楼面和地面地震反应谱的差别。结果表明:楼面地震系数和楼面动力放大系数最大值分别存在大于和小于地面地震系数和地面动力放大系数最大值的情况，最大相差近1倍；楼面地震反应谱的特征周期均大于地面地震反应谱的特征周期，最大相差60%以上；地面与楼面动力放大系数谱的谱型在某些条件下存在明显不同，楼面动力放大系数谱的第二谱峰值有可能很大，甚至出现接近第一峰值的情况，而地面地震反应谱无此现象；计算楼层附属结构地震作用时，需根据主体结构考虑地震系数、动力系数、特征周期及动力放大系数谱谱型的变化。

Analysis of Seismic Response Spectra Characters of Super high Rise Steel Structure

In order to analyze the floor response characteristics spectrum of super high rise building, floor response spectrums were calculated by inputting different ground motions to China Financial Information Mansion. The floor and ground response spectrums were compared from the following four aspects: seismic coefficient, dynamic amplification coefficient, characteristic period and shapes of response spectrums. The results show that the floor seismic coefficient and the magnification coefficient are greater or smaller than the corresponding ground one respectively, the biggest difference of which is nearly 1 time; all the floor characteristic periods are greater than those of the ground, the biggest difference of which is over 60%; there are obvious differences between the shapes of floor and ground dynamic magnification factor spectra under some conditions, the second peak of the former may be very large, even near to the first peak, while the latter one has no such phenomenon. Therefore, when the seismic response of floor subsidiary structure is calculated, it is necessary to consider the change of floor seismic coefficient, dynamic magnification factor, characteristic period and spectra shape based on the main structure.