中国西南地区Arias强度衰减特性研究

Arias intensity, as a parameter descripting ground motion amplitude and duration characteristics, has good correlation with earthquake damage such as landslide and sand soil liquefaction, and has important application value in the rapid assessment of earthquake disaster, seismic landslide hazard analysis and so on. At present, China is still in the initial stage of the application of Arias intensity in the study of seismic disaster mechanism. Most recent researches are focus on distribution characteristics in one earthquake event, lacking of study on the attenuation law in a large region as well as its discrete characteristics. The present situation leads to the urgency needs for the Arias intensity attenuation relationship in the earthquake engineering application. The mountainous area of Southwest China is one of the most domestic seismically active regions, making this area facing high risk of earthquake landslide damage. It is of great practical significance to study the Arias intensity attenuation law of Southwest China using high quality strong-motion records collected in this region. We supposed to carry out study on the attenuation characteristics of Arias intensity in Southwest China using regression analysis, and on the influence of hanging-wall effect, soil site effect and focal mechanism based on residual analysis, as well as on its discrete characteristics. Relevant research results could be applied in ground motion research, earthquake disaster assessment and earthquake engineering research.

Arias强度作为一种能够描述幅值及持续时间特性的地震动参数，与地震滑坡、砂土液化等地震灾害具有良好相关性，在地震灾情快速评估、地震滑坡危险性分析等方面具有重要应用价值。目前我国对Arias强度衰减特征的研究处于起步阶段，主要成果集中于单个地震的分布特性研究，鲜有对区域范围的衰减规律及其离散特性的研究，因而在工程应用上对Arias强度衰减关系的需求存在紧迫性。我国西南地区山地覆盖广而强震危险性高，面临巨大地震滑坡风险。利用西南地区已积累的一批高质量强震记录研究区域内Arias强度衰减规律具有很强的实际意义。本项研究拟采用统计回归方法作为技术手段，研究我国西南地区Arias强度均值随震级、距离的衰减特性。应用残差分析研究上下盘效应、土层场地效应、震源机制等对Arias强度的影响，同时对Arias强度的离散特征进行研究。相关研究成果可供地震动研究、灾情评估及地震工程参考使用。

Arias强度作为一种能够描述幅值及持续时间特性的地震动参数，与地震滑坡、沙土液化等地震灾害具有良好相关性，在地震再请快速评估、地震滑坡危险性分析等方面具有重要应用价值。我国西南地区山地覆盖广而强震危险性高，面临巨大地震滑坡风险。.本项研究，利用国际上和我国西南地区已积累的一批高质量强震记录，采用统计回归方法作为技术手段，分析了水平向Arias强度随震级、距离的衰减特性，重新拟合了我国西南地区水平向Arias强度衰减模型，并以模型化的方式体现了上下盘效应、土层场地效应、震源机制等的影响。同时利用残差分析对Arias强度的离散性进行了研究。结果显示Arias强度与高频地震动具有很高的相关性，离散标准差随震级、距离变化不明显。.本项研究相关成果可供地震动研究、灾情评估及防震工程参考使用。