适用于结构时程分析法的输入地震波

本文对建筑结构抗震设计时程法所需的输入地震波提出一种基于规范反应谱的、与设防烈度、场地条件、设计近震或远震、结构自振特性有关的选择原则和方法。按远、近震和四类场地标定了反应谱、延性谱和积累损伤谱。通过对六幢不同高度的剪切和弯曲型结构模型的弹塑性分析,表明离差很小。建议在进行结构时程法分析时,按地震加速度反应谱特定的分布规律选择4条加速度记录作为输入计算。两个实际的例子表明按上述方法计算的结果与按底部剪力法计算的结果基本相符。

THE EARTHQUAKE INPUT FOR TIME-HISTORY ANALYSIS OF STRUCTURE

The paper presents the principle and methodology of the earthquake input for time-history seismic analysis of building structure that is based in design response spectrum and related to the seismic intensity, site condition, source mechanism and natural period of the structure. Ductility demand spectrum and accumulative damage spectrum of four classes of site under far-field and near-field earthquakes are identified. Elasto-plastic time-history analysis were carried out individually for six structure models, presenting bending pattern and shearing pattern of high,medium and low buildings. The results show a low deviation of statistics in the maximum inner-force and displacement of the model structures under the same group of input. As a result, a group of four accelerograms whose characteristic periods of spectra obey a particular distribution law, are suggested as the earthquake input for time-history analysis of structures. Two example buildings are taken for time-history analysis. The elastic responses of inner force and displacement calculated by both of the code-based response spectrum method and time-history method show a fine agreement.