日本福岛县两次复发地震强震动特征对比研究  

Comparative study on strong motion characteristics of recurrent earthquakes in Fukushima Prefecture,Japan

作　　者：宋泉 周宝峰[1] 李春果 温瑞智[1] SONG Quan;ZHOU Baofeng;LI Chunguo;WEN Ruizhi(Key Laboratory of Earthquake Engineering and Engineering Vibration,Institute of Engineering Mechanics,China Earthquake Administration,Key Laboratory of Earthquake Disaster Mitigation,Ministry of Emergency Management,Harbin 150080,China)

机构地区：[1]中国地震局工程力学研究所地震工程与工程振动重点实验室,地震灾害防治应急管理部重点实验室,黑龙江哈尔滨150080

出　　处：《世界地震工程》2022年第4期195-203,共9页World Earthquake Engineering

基　　金：国家重点研发计划项目政府间国际科技创新合作重点专项(2018YFE0109800);黑龙江省自然科学基金联合引导项目(JJ2022LH0668)。

摘　　要：本文以2021年2月13日和2022年3月16日日本福岛近海区域发生的M_(w)7.0和M_(w)7.3地震强震动数据为基础,从地震动的幅值、频谱、持时以及衰减关系等方面对比分析了强震动特征,解释了复发性地震的相似性,研究表明:当周期大于0.8 s时,两个台站记录的加速度反应谱低于设计谱数值,对于长周期结构影响较小;随着场地和断层距的变化,同一台站在两次地震中加速度反应谱峰值对应的周期并没有发生明显的变化,在长周期部分,断层距较近的台站随着周期的增加反应谱下降的更快;两次地震中相应的PGA和PGV幅值呈对数线性关系;在等效卓越频率方面,2.0~4.0 Hz范围内的离散点相对较少,解释了结构破坏较轻的现象;两次地震持时的回归曲线趋势相同,衰减相对较慢。Based on the strong motion data of M_(w)7.0 and M_(w)7.3 earthquakes that occurred on February 13,2021 and March 16,2022 in the offshore area of Fukushima,Japan,the characteristics of strong motion are compared and analyzed from the amplitude,frequency spectrum,duration and attenuation relationship of ground motions,and the similarity of recurrent earthquakes is explained.The results show that:when the period is larger than 0.8s,the acceleration response spectra of the two stations records are lower than the design spectrum,which has little ef⁃fect on the long⁃period structure.With the change of site and fault distance,the period corresponding to the peak of the velocity response spectrum of the same station during the two earthquakes does not change significantly.In the long period part,the response spectrum of the station with the fault distance closer decreases faster with the in⁃crease of the period.The amplitude of PGA and PGV in the two earthquakes show logarithmic linear relationship.In term of equivalent predominant frequency,there are relatively few discrete points in the range of 2.0-4.0Hz,which explains the phenomenon of lighter structural damage.The regression curves of the two earthquakes have the same trend and the attenuation is relatively slow.

关 键 词：日本地震 震害影响 反应谱 幅值 持时 衰减关系 

分 类 号：P315[天文地球—地震学]