近、远场长周期地震动界定及分类研究  

Definition and classification of near and far field long period ground motions

作　　者：张亮泉[1] 于建杰 ZHANG Liangquan;YU Jianjie(School of Civil Engineering,Northeast Forestry University,Harbin 150000,China)

机构地区：[1]东北林业大学土木工程学院

出　　处：《自然灾害学报》2019年第2期29-36,共8页Journal of Natural Disasters

基　　金：中央高校基本科研专项基金项目(2572014CB23)~~

摘　　要：目前,针对近断层脉冲型长周期地震动和远场类简谐长周期地震动的界定主要根据时程特点进行,在界定时主观性较强,并不具有普适性,因此采用合理的量化标准来对这两类长周期地震动界定有着重要意义。为解决这一问题,本文以1999年Chi-Chi地震长周期地震动为样本,提出了一种结合震中距、场地类别和长周期分量能量累积谱90%能量持时归一化系数T0.9为三参数的长周期地震动的分类方法。该方法首先利用希尔伯特-黄变换(HHT)求得参数T0.9,然后利用该参数判断长周期地震动是否具有脉冲特性。然后,根据对Chi-Chi长周期地震动的分析,结合不同场地类别下震中距及T0.9的差异来区分远、近场长周期地震动。最后,以2008年汶川地震渭河盆地中收集到的长周期地震动为例,验证了所提分类方法的有效性。At present,the definition of near-fault pulse-type ground motion and far-field harmonic-like ground motion mainly depends on the eye view method,which is defined according to the time-course characteristics.It is subjective and not universal in definition.The standard of reasonable quantification is of great significance for the definition of two types of long-period ground motions.In order to solve this problem,this paper takes the Chi-Chi earthquake long-period ground motion as a sample,and proposes a combination of epicenter distance,site category and long-period component energy accumulation spectrum 90%energy holding time normalization coefficient T 0.9 three parameters classification.The method first uses the Hilbert Huang transform to obtain the parameter T 0.9,and then uses this parameter to determine whether the long-period ground motion has a pulse characteristic.According to the analysis of Chi-Chi long-period ground motion,the far and near-field long-period ground motions are distinguished by the difference between the two types of long-period ground motions under different field categories.Taking the long-period ground motion collected in the Weihe Basin of Wenchuan Earthquake as an example,the validity of the proposed classification method is verified.

关 键 词：希尔伯特-黄变换(HHT) 长周期地震动 分类标准 震中距 分布关系 

分 类 号：P315.3[天文地球—地震学] X43[天文地球—固体地球物理学]