NGA数据库的多圆组合地震动衰减模型

摘要

为系统分析多圆组合地震动衰减关系模型的可靠性,在应用汶川地震的地震动衰减关系验证该模型合理性的基础上,本文结合NGA(新一代地震动衰减模型)项目的强大数据库,讨论了多圆组合模型中子断层的划分规则和子源震中距的求法.拟合出了NGA数据库的多圆组合地震动衰减关系,并分别讨论了断层类型,上、下盘效应,覆盖层厚度对拟合地震动的影响;比较了多圆组合模型与NGA模型(BA08)的回归结果,并讨论了两者之间存在差距的原因.结果表明,多圆组合模型对NGA数据库地震动的拟合结果比较理想.多圆组合模型形式简单,拟合精度较高,并具有一定的理论依据,通过本课题的研究,为其进一步的发展奠定了基础.%To analyze the reliability of the multi-circle ground motion attenuation model, of which the rationality has been demonstrated by the ground motion attenuation relation analysis of the Wenchuan earthquake, the measure of dividing fault and getting sub-source epicentral distance were studied based on NGA database.The multi-circle ground motion attenuation relationship of NGA database was fitted, and the types of fault, hanging/foot wall and coverage thickness on fitting ground motions were discussed respectively.The fitting results of multi-circle model have been compared with that of NGA model(BA08), and the difference between the two results was analyzed.The results show that the multi-circle model gives a good fitting result for spatial distribution of ground motion of NGA database.Due to the simple form and high precision, the multi-circle model with specific theoretical basis would have further development through this project.