摘要
利用黄土高原44次地震的烈度等值线图等资料,选用椭圆限定模型,运用两次加权、两步回归法分别建立黄土高原西区和东区的地震烈度衰减关系。通过增加拟合限定条件,实现长轴和短轴在震中和远场的烈度值大致相等的要求。与其他区域的地震烈度衰减关系对比显示,黄土高原地区烈度衰减关系具有显著的区域性特点。在大多数情况下,相同距离处,黄土高原西区的烈度值高于青藏区,最大差值可达0.8;当震中距较小时,黄土高原东区的长轴和短轴烈度值均低于东部强震区,因黄土高原东区烈度的衰减速率较慢,随着距离增大,其烈度值逐渐超过东部强震区。
This study systematically collected and organized seismic intensity isolines and relevant damage investigation data for 44 seismic events in the Loess Plateau region of China.We used a constrained model of seismic intensity ellipses and applied a two-step regression with double weighting to establish seismic intensity attenuation relationships for the western and eastern regions of the Loess Plateau.We ensured that the long and short axes of the intensity ellipses at epicentral and far-field distances had approximately equal intensity values by imposing additional fitting constraints.A comparative analysis of seismic intensity attenuation relationships in other regions revealed distinct regional characteristics in the Loess Plateau area.In most cases,at equivalent distances,the intensity values in the western region of the Loess Plateau are higher than those in the Qinghai—Xizang Plateau,with a maximum difference of 0.8.For short epicentral distances,the intensity values along the long and short axes in the eastern region of the Loess Plateau are lower than those in China's eastern strong earthquake zone.As the distance increases,the intensity values in this region gradually surpass those in the strong earthquake zone of eastern China due to the slow attenuation rate of intensity in the Loess Plateau's eastern region.
作者
万卫
薄景山
彭达
李孝波
WAN Wei;BO Jingshan;PENG Da;LI Xiaobo(Key Laboratory of Earthquake Engineering and Engineering Vibration,Institute of Engineering Mechanics,CEA,Harbin 150080,Heilongjiang,China;Key Laboratory of Earthquake Disaster Mitigation,Ministry of Emergency Management,Harbin 150080,Heilongjiang,China;College of Geological Engineering,Institute of Disaster Prevention,Sanhe 065201,Hebei,China;Hebei Key Laboratory of Earthquake Disaster Prevention and Risk Assessment,Sanhe 065201,Hebei,China)
出处
《地震工程学报》
北大核心
2025年第4期886-900,共15页
China Earthquake Engineering Journal
基金
中国地震局地震工程与工程振动重点实验室重点专项(2020EEEVL0201)
中央高校基本科研业务费专项资助(ZY20215128)
河北省教育厅科学研究项目资助(QN2021308)。
关键词
黄土高原
地震烈度
衰减关系
限定模型
对比分析
the Loess Plateau
seismic intensity
attenuation relationship
constrained model
comparative analysis
