近断层竖向地震动特征统计分析  

Statistical analysis of vertical ground motion characteristics in near-fault regions

作　　者：李宁[1,2,3] 刘洪国[1,2] 刘平 李忠献[1,2,3] 谢礼立[5] Li Ning;Liu Hongguo;Liu Ping;Li Zhongxian;Xie Lili(School of Civil Engineering,Tianjin University,Tianjin 300072,China;Key Laboratory of Coast Civil Structure Safety of the Ministry of Education,Tianjin University,Tianjin 300072,China;Key Laboratory of Earthquake Engineering Simulation and Seismic Resilience of China Earthquake Administration,Tianjin University,Tianjin 300350,China;Ren’ai College,Tianjin University,Tianjin 301636,China;Institute of Engineering Mechanics,China Earthquake Administration,Harbin 150090,China)

机构地区：[1]天津大学建筑工程学院,天津300072 [2]天津大学滨海土木工程结构与安全教育部重点实验室,天津300072 [3]天津大学中国地震局地震工程综合模拟与城乡抗震韧性重点实验室,天津300350 [4]天津大学仁爱学院,天津301636 [5]中国地震局工程力学研究所,黑龙江哈尔滨150090

出　　处：《土木工程学报》2020年第10期120-128,共9页China Civil Engineering Journal

基　　金：国家重点研发计划(2018YFC1504306,2016YFC0701108);国家自然科学基金(51678407,51427901)。

摘　　要：为研究近断层地区的竖向地震动特性,基于环太平洋地震工程研究中心(PEER)数据库选取890组强地震动,研究了地震动竖向与水平加速度分量峰值比aV/aH与矩震级、断层距、场地条件和断层类型的统计规律,给出近断层竖向加速度与水平加速度峰值比aV/aH的合理取值。采用基于能量的识别方法判定近断层地震动是否包含脉冲,分别研究竖向脉冲和水平脉冲参数与地震参数关系并对比了竖向脉冲和水平脉冲的速度峰值及周期的衰减关系。结果表明:近断层区域竖向加速度与水平加速度峰值比aV/aH受地震参数影响,规范建议值2/3会低估近断层竖向地震;相比较于水平脉冲,竖向脉冲数量少且分布范围小,水平脉冲和竖向脉冲的峰值、周期也存在差异。To study the vertical ground motion characteristics of the near-fault regions, 890 sets of ground motions were selected from the ground motion database of the Pacific Earthquake Engineering Research Center(PEER).The statistical relationship of the vertical-to horizontal-peak acceleration ratio aV/aH with respect to the moment magnitude, the fault distance, the site conditions and the fault mechanism is analyzed, and a reasonable value of aV/aH in the near-fault regions is suggested.In addition, the energy-based identification method is used to classify whether the near-fault ground motion includes pulses or not.The relationships between vertical/horizontal pulse parameters and the seismic characteristic parameters are studied respectively, and the attenuation relationships of the peak velocity/period between the vertical pulse and the horizontal pulse are compared.The results show that the vertical peak acceleration and horizontal peak acceleration ratio a_V/a_H in the near-fault regions is affected by the seismic characteristic parameters.The specified value of 2/3 in the design code may underestimate the vertical ground motion in the near-fault regions.Compared with the horizontal pulse, the number of the vertical pulses is relatively small and the distribution of vertical pulses is narrow.In addition, differences in the peak velocity and periods of the horizontal and vertical pulses may also be observed.

关 键 词：近断层 竖向地震 加速度峰值比a_V/a_H 竖向脉冲 脉冲分布 

分 类 号：P315.9[天文地球—地震学] TU318.1[天文地球—固体地球物理学]