中文摘要：

反应谱特征周期即反应谱的第二拐点周期，是工程抗震设计的关键参数。收集了美国西部825条强地震记录并进行统计分析，结果表明：（1）反应谱特征周期随着场地的变软，震级的增大而增大，趋势较明显，但是特征周期与震中距和震源深度的线性相关性不明显；（2）竖向特征周期低于水平向特征周期，其差值随着场地的变软而增大；（3）与我国规范相比较，实际统计远场水平特征周期高于我国《建筑抗震设计规范》（GB50011-2010）中的设计特征周期，实际统计竖向特征周期与此规范规定基本相同。该统计分析结果为大型或重要建筑结构抗震设计反应谱确定和抗震设计规范中设计特征周期的确定具有参考价值。

英文摘要：

Characteristic period of response spectrum is an important characteristic parameter for engineering seismic design, it is also the second turning point period of response spectrum. This paper has collected 825 strong earthquake records in western United States and has carried on the statistical analysis. The analysis results indicate that （ 1 ） the characteristic period of response spectrum increases when the site becomes soft or when the magnitude increases, the trend is more obvious; But the linear relation of characteristic period of response spectrum with the epicenter distance and focal depth are not obvious. （2） The vertical characteristic period is lower than the horizontal characteristic period, and the difference value increases with the site becoming softer. （3） Compared with the Chinese code, the actual statistical horizontal characteristic period which is far from the fault is higher than the provided value by Code for Seismic Design of Buildings （ GBS0011--2010 ） in China： The actual statistical vertical characteristic period and the provided value in Chinese code are basically the same. The statistical analysis results in this paper have a reference value for determining characteristic period of response spectrum for large or important building structure and Code for Seismic Design of Buildings.