我国黄土地区土层地震动峰值加速度衰减关系研究

Study on the Ground-motion Attenuation Relation in the Loess Region of China

收集、筛选并整理了2001—2019年我国黄土地区发生的141次M_(S)2.4~6.7地震的1092条台站记录,选取台站中两水平向峰值加速度偏高的值作为拟合值,采用两步回归法拟合得到了我国黄土地区水平向土层地震动衰减关系,分析了地震动残差随震级和距离的分布趋势,并将衰减关系和已有研究成果进行了对比。结果表明:绝大多数实测值均在拟合峰值加速度衰减曲线±1倍标准差范围以内,模型能较好地反映中国黄土地区峰值加速度随距离衰减的趋势。

In this paper,1092 pieces of records of 141 seismic events occurring in the Loess region of China from 2001 to 2019 were sorted out.The higher values of the two horizontal peak accelerations are selected as the fitting values,and the Two-step Regression method is used to obtain the horizontal ground-motion attenuation relation in the Loess region of China.The distribution of residuals related with magnitude and distance is analyzed,and the attenuation relation proposed in this paper is compared with the ones proposed by other researchers.The results show that most of the observed values are within the range of±1 standard deviation of the acceleration attenuation curve,and the model proposed in this paper can better reflect the peak acceleration's attenuation trend with distance in the Loess region of China.