摘要
选取国内外13次地震的26个近断层地震动记录,研究适用于长周期结构的地震动强度指标.采用时程分析法计算了自振周期3.0～8.0 s的单自由度结构的加速度、速度和位移响应,研究了峰值加速度、均方根加速度、峰值速度、均方根速度、峰值速度与峰值加速度比、峰值位移和均方根位移与这些响应最大值的相关性.在此基础上以宿迁某高层隔震建筑为对象,进一步考察实际长周期结构的最大地震响应与地震动强度指标的相关性.研究结果表明:不同地震动强度指标与长周期结构最大响应的相关性差别很大,加速度型地震动强度指标的相关性最差,速度型强度指标随着结构周期的增加其相关性愈差,位移型强度指标随着结构周期的增加其相关性愈好.相比峰值加速度和峰值速度强度指标,近断层地震动作用下长周期结构时程分析时,选择位移型地震动强度指标用于选择和调整地震动输入更为合理.
26 suites of near-fault ground motions which are collected in the 13 earthquakes were adopted to investigate the ground motion intensity indices applicable for long period structures. The acceleration, velocity and displacement responses of SDOF systems with the natural period from 3.0 to 8.0 s were calculated using the time history analysis. Then the correlations between the maximum responses and the ground motion intensity indices including the peak ground acceleration, root-mean- square of acceleration, peak ground velocity, root-mean-square of velocity, the ratio of peak ground velocity to peak ground acceleration, peak ground displacement, root-mean-square of displacement were analyzed. Furthermore, the correlation between the maximum responses of a high-rise isolation building in Suqian and these intensity indices were analyzed. The results show that the different intensity indices have various correlations with the maximum responses of long period structures. The correlations of acceleration-related intensity indices are the worst and the correlations of velocity-re- lated intensity indices become worse with the increase of period, whereas the correlations of displacement-related intensity indices show high linearity with the increase of period. In contrast to the peak ground acceleration and peak ground velocity, displacement-related intensity indices are more reason- able to be used for selecting and adjusting ground motion inputs for time history analysis of long period structures subjected to near-fault motions.
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2013年第1期203-208,共6页
Journal of Southeast University：Natural Science Edition
基金
国家自然科学基金资助项目(51178100)
"十二五"交通运输重大科技专项资助项目(2011318223170)
江苏省自然科学基金资助项目(BK2011141)
江苏省高校"青蓝工程"优秀青年骨干教师资助项目
东南大学重大科学研究引导基金资助项目
关键词
地震动强度指标
近断层地震动
时程分析
相关系数
ground motion intensity index
near-fault ground motion
time history analysis
correlation coefficient
