地震动参数之阿里亚斯烈度和累积绝对速度的特征及其在概率地震危险性分析中的应用

发布时间：2018-10-14 12:54

【摘要】：地震动参数是表征地震动特性(振幅、频率和持时)的重要度量参数。目前使用最多的地震动参数主要有峰值加速度和谱加速度等,然而任何单一地震动参数都不能全面有效地反映所有的地震动破坏特征(如峰值加速度仅反映振幅)。为了更加全面的描述地震动特征及其潜在的破坏作用,满足工程应用的需求,科学家们一直在寻找能够表征地震动多种属性和特定地震破坏的地震动参数。经研究发现,阿里亚斯烈度Ia(Arias intensity)、累积绝对速度CAV(Cumulative absolute velocity)及Newmark位移在地震诱发滑坡预测、沙土液化评估、地震灾害损失估计以及地震危险性分析等方面优于峰值加速度,因此开展Ia、CAV和Newmark位移的特征研究及与其相关的地震危险性分析方法研究对于拓展我们对地震动特性的认识和提高地震灾害预测水平具有重要的科学意义和应用价值。本文我们根据汶川地震的177个台站的528条可用记录的强震数据,在对地震记录进行基线校正后计算了地震动参数Ia、CAV及Newmark位移,并研究了这些地震动参数的相关特征,最后我们还开展了基于Ia、CAV及Newmark位移的概率地震危险性分析方法研究。我们研究了汶川地震Ia的空间分布特征、衰减特征、近断层特征以及Ia与其他地震动参数的相关性。在空间分布特征研究中,我们比较了竖向和水平向Ia值的差异,统计了二者的比值分布及随距离的变化特征;对于垂直断层走向和平行断层走向的Ia值也做了同样的工作。在衰减特征方面,我们主要研究了3种场地类型下的Ia衰减特征及其与现有Ia预测模型的比较,指出了他们之间的差异并分析了导致差异的原因。在近断层特征方面,主要研究了上盘效应和方向性效应对Ia的影响。最后我们研究了Ia与PGA和Housner烈度的相关性,建立了Ia与PGA和Housner烈度之间的经验关系式,并分析了场地条件对地震动参数之间相关性的影响。我们对CAV也同样研究了其空间分布特征、衰减特征、近断层特征以及CAV与其他地震动参数的相关性。特别地,我们还研究了标准CAV的衰减特征和其与PGA的相关性,分析了场地条件对它们的影响。另外,我们简要分析了汶川地震Newmark位移的衰减特征及其与PGA和Ia的相关性。本文中我们还开展了基于Ia、CAV的概率地震危险性分析方法研究,开展了基于Newmark位移的概率地震滑坡危险性分析方法研究,梳理了相关的理论、方法,建立了相关的技术框架,编制了计算程序并在典型地区进行了试算。本文的研究对我们认识汶川地震乃至我国西部地震地质构造环境下地震的Ia、CAV及Newmark位移的相关特征具有重要的科学意义。建立的相关概率地震危险性分析方法的技术框架对于提高我国的概率地震危险性分析水平和地震灾害预测水平具有重要的应用价值。
[Abstract]:Seismic parameters are important parameters to characterize the characteristics of ground motion (amplitude, frequency and duration). At present, the most commonly used parameters of ground motion are peak acceleration and spectral acceleration. However, any single ground motion parameter can not fully and effectively reflect all the damage characteristics of ground motion (for example, the peak acceleration only reflects the amplitude). In order to fully describe the characteristics of ground motion and its potential damage and meet the needs of engineering applications, scientists have been looking for seismic parameters that can represent the various properties of ground motion and specific earthquake damage. It is found that Avias intensity Ia (Arias intensity), accumulative absolute velocity CAV (Cumulative absolute velocity) and Newmark displacement are superior to peak acceleration in earthquake induced landslide prediction, sand liquefaction assessment, earthquake disaster loss estimation and seismic hazard analysis. Therefore, the research on the characteristics of Ia,CAV and Newmark displacements and the methods of seismic hazard analysis related to them have important scientific significance and application value in expanding our understanding of seismic characteristics and improving the level of earthquake disaster prediction. In this paper, based on the data of 528 strong earthquakes available from 177 stations in Wenchuan earthquake, we calculate the ground motion parameters Ia,CAV and Newmark displacement after the baseline correction of the seismic records, and study the relevant characteristics of these seismic parameters. Finally, the probabilistic seismic hazard analysis method based on Ia,CAV and Newmark displacements is studied. We have studied the spatial distribution, attenuation, near fault and the correlation between Ia and other seismic parameters of Wenchuan earthquake. In the study of spatial distribution characteristics, we compare the differences between vertical and horizontal Ia values, and calculate the ratio distribution and variation characteristics with distance, and do the same work for the Ia values of vertical fault strike and parallel fault strike. In terms of attenuation characteristics, we mainly study the attenuation characteristics of Ia under three site types and their comparison with existing Ia prediction models, point out the differences between them and analyze the causes of the differences. In terms of near-fault characteristics, the effects of upper disc effect and directional effect on Ia are mainly studied. Finally, we study the correlation between Ia and PGA and Housner intensity, establish the empirical relationship between Ia and PGA and Housner intensity, and analyze the influence of site conditions on the correlation between ground motion parameters. We also study the spatial distribution, attenuation, near-fault characteristics of CAV and the correlation between CAV and other seismic parameters. In particular, we also study the attenuation characteristics of standard CAV and its correlation with PGA, and analyze the influence of site conditions on them. In addition, we briefly analyze the attenuation characteristics of Newmark displacement in Wenchuan earthquake and its correlation with PGA and Ia. In this paper, the probabilistic seismic risk analysis method based on Ia,CAV and the probabilistic landslide hazard analysis method based on Newmark displacement are also studied, and the relevant theories and methods are combed, and the relevant technical framework is established. A calculation program is compiled and a trial calculation is carried out in a typical area. The study in this paper is of great scientific significance for us to understand the characteristics of the Ia,CAV and Newmark displacements of earthquakes in Wenchuan earthquake and the earthquake geological environment in the west of China. The technical framework of the related probabilistic seismic hazard analysis method has important application value in improving the level of probabilistic seismic hazard analysis and earthquake disaster prediction in China.
【学位授予单位】：中国地震局地球物理研究所
【学位级别】：博士
【学位授予年份】：2017
【分类号】：P315

【参考文献】