Seismic Risk Analysis of Critical Engineering Structures

地震是最具破坏性的自然灾害之一。由于近几十年来发生了多起破坏性地震，对重要工程结构进行地震风险分析已成为地震工程领域最重要和最热门的课题之一。世界范围内的核能工业正在对核电站（NPP）系统的地震危害和风险进行前所未有的广泛重新评估。此外，核能监管机构和公用事业公司正在对现有的核电站地震风险评估方法进行严格审查。在现有的地震危险性分析方法中，已经认识到一些缺点。 本研究的目的是发展一个现代地震风险分析的概率框架。这将包括通过对主要和次要结构的反应分析，到关键工程结构系统的矢量值地震脆弱性和风险分析，制定符合矢量值概率地震危险分析的新设计谱。 拟议的研究将研究一个新开发的矢量值均匀危险谱（VUHS）的频谱形状，以进一步改善其生成，并校准VUHS的地震危险水平，使其可以在抗震设计规范中实施。将为土壤-结构相互作用分析开发模拟空间变化土壤特性的综合随机场模型和合成空间变化地面运动的方法。本研究将发展以关键地震动参数向量为基础的向量值地震易损性分析及向量值地震风险分析，以提供更严谨及准确的关键工程结构地震风险评估。 这种基于向量值分析的框架将大大改进抗震设计规范。所开发的方法可用于设计新的和评估现有的关键工程结构，以符合现代地震安全标准。

Earthquake is one of the most destructive natural disasters. Since several destructive earthquakes have occurred in recent decades, seismic risk analysis for critical engineering structures has become one of the most important and popular topics in earthquake engineering. Nuclear energy industries world-wide are launching an unprecedented and extensive re-evaluation of seismic hazards and risk to nuclear power plant (NPP) systems. Furthermore, nuclear energy regulators and utilities are taking a critical look at the existing methods of estimating seismic risk of NPPs. A number of shortcomings have been recognized in the existing methods of seismic risk analysis. The objective of this research is to develop a modern probabilistic framework of seismic risk analysis. This would include development of a new design spectrum consistent with vector-valued probabilistic seismic hazard analysis, through the response analysis of primary and secondary structures, to the vector-valued seismic fragility and risk analyses of critical engineering structural systems. The proposed research will study the spectral shape of a newly developed vector-valued uniform hazard spectrum (VUHS) to further improve on its generation, and to calibrate the seismic hazard level of the VUHS so that it can be implemented in seismic design codes. Comprehensive random field models to model spatially varying soil properties and approaches to synthesize spatially varying ground motions will be developed for soil-structure interaction analysis. The proposed research will develop vector-valued seismic fragility analysis and vector-valued seismic risk analysis, in terms of vectors of key ground motion parameters, to provide more rigorous and accurate seismic risk estimations of critical engineering structures. This framework based on vector-valued analysis will substantially improve seismic design codes. The methodologies developed can be used to design new and to assess existing critical engineering structures to comply with modern standards for seismic safety.