2024年1月1日日本Mw7.5级能登半岛地震记录特征统计分析  

Characteristics statistical analysis for records of Mw7.5 earthquake occurred at Noto Peninsula in Japan on January 1,2024

作　　者：方登甲 孙纬宇 周宇 狄生奎 FANG Dengjia;SUN Weiyu;ZHOU Yu;DI Shengkui(School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;College of Civil Engineering,Anhui Jianzhu University,Hefei 230601,China)

机构地区：[1]兰州交通大学土木工程学院,兰州730070 [2]安徽建筑大学土木工程学院,合肥230601

出　　处：《振动与冲击》2024年第23期155-163,185,共10页Journal of Vibration and Shock

基　　金：甘肃省道路桥梁与地下工程重点实验室项目(2023054);国家自然科学基金项目(52208392);甘肃省住建厅科研项目(JK2023-03)。

摘　　要：北京时间2024年01月01日15时10分(当地时间16时10分)左右,日本石川县能登半岛(Noto Peninsula)附近发生了Mw7.5(或Mj7.6)级地震,造成人员伤亡和财产损失。通过选择的411组强震记录数据,研究了地震动峰值加速度与加速度反应谱峰值随震中距的衰减特征、加速度记录竖向与水平分量的幅值比、强震持时特征以及与周期相关的特性等,并探讨了典型强震记录的时频特性。结果表明:此次地震震中附近地震动记录峰值较大,且强震范围沿半岛西侧东北-西南向分布较广,影响范围较大。但地震动强度在震中距大于30 km以后基本呈直线下降,衰减速度较快。此次统计的地震动所有记录中明显表现出长持时特征,最短的D _(s5-95)持时也有13.38 s,且随着震中距的增加,持时也相对在增加,且在震中附近的台站时程记录中发现“双峰”现象,造成的该现象的原因可能与地层断裂是双向且断层面较长有关。另外,地震动记录中的低频含量相对较为丰富,特别是当震中距大于100 km以后,长周期特征较为明显,这与软土场地土条件以及震群的特点有关。揭示的特征可为工程结构的抗震设防提供参考。At around 15:10 Beijing time(16:10 Tokyo time)on January 1,2024,a magnitude of Mw7.5(or Mj7.6)earthquake occurred at Noto Peninsula in Ishikawa Prefecture,Japan to cause casualties and property damage.Here,by selecting 411 sets of strong earthquake records data,decay characteristics of ground motion peak acceleration and acceleration response spectrum peaks with respect to distance from epicenter,amplitude ratios of vertical and horizontal components of ground motion acceleration records,duration characteristics of strong earthquakes and characteristics related to periods were studied,and time-frequency characteristics of typical strong earthquake records were also explored.The results showed that peak value of seismic motion recorded near epicenter of this earthquake is larger,and the strong earthquake range is widely distributed in northeast-southwest direction along west side of peninsula,the influence range is larger;but the intensity of seismic motion generally decreases linearly and decays rapidly after the distance from epicenter is larger than 30 km;records collected here obviously exhibit long-term duration characteristics,the shortest duration D _(s5-95) is 13.38 s,with increase in the distance from epicenter,the duration also increases relatively;a“double-peak”phenomenon appears in time history records of station near epicenter,it may be related to the presence of bi-directional fault rupture with longer fault planes;low-frequency content in seismic records is relatively more abundant,especially when the distance from epicenter is larger than 100 km,long-period characteristics are more obvious,these are related to soil conditions of soft soil sites and features of earthquake clusters;the revealed features can provide a reference for aseismic fortification of engineering structures.

关 键 词：能登半岛地震 强震记录 周期特性 时频特性 

分 类 号：TU202[建筑科学—建筑设计及理论] P315.9[天文地球—地震学]