Seismic Risk Analysis and Design of Nuclear Power Plants

核电厂地震风险分析与设计

• 批准号: RGPIN-2018-04031
• 负责人: Xie, WeiChau
• 金额: $ 4.52万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=748833
• 关键词: Seismic; Risk; Analysis; Design; Nuclear

Earthquakes are among the most destructive natural disasters. In response to the occurrence of several destructive earthquakes in recent decades, the nuclear industry is taking a critical look at the existing methods of assessing seismic risk of nuclear power plants (NPPs). A number of deficiencies have been recognized in the existing methods of seismic risk analysis. In an NPP, there are a large number of safety-related structures, systems, and components (SSCs). The most effective approach to ensure safe shutdown and to prevent accidents during an earthquake is to ensure adequate safety margins for these SSCs through seismic design and seismic risk assessment. The long-term objective of my research program is to establish a systematic framework for probabilistic seismic risk analysis and design of NPPs. Through continued collaboration with nuclear industrial partners, the proposed research will satisfactorily address two important issues that have challenged earthquake engineering and the nuclear industry for decades: (1) Generating drift-free, consistent, and perfectly spectra-compatible tri-directional time histories; (2) A direct method for generating Floor Response Spectra (FRS) with flexible foundation and considering soil-structure interaction (SSI).Time history analysis has been widely used in practice, for example, in nonlinear dynamic analysis and analysis of multi-supported systems. Using eigenfunction expansions and the method of influence matrix, the proposed research will develop an efficient and easy to use algorithm to generate drift-free, consistent, and perfectly spectra-compatible tri-directional ground motion time histories. The algorithms and software developed are of great practical importance in earthquake engineering.Accurate determination of FRS, used as a seismic input to SSCs, is one of the most critical tasks in seismic analysis. Overly conservative FRS increase the cost, while non-conservative FRS compromise safety. A direct spectra-to-spectra method for generating FRS that is accurate and efficient has recently been developed by my research group. It is suitable for generating FRS for fixed-base structural models and has been successfully applied in a commercial project by Candu Energy Inc. In the proposed research, the direct method will be extended to account for flexible foundation and SSI. The effect of the uncertainty of soil properties on SSI analysis will be accurately addressed and a complete probabilistic method will be developed to model the uncertainty. This research will provide advanced methodologies and modern tools to assess seismic margin and risk of existing SSCs in refurbished NPPs and to design new SSCs in new NPPs to ensure seismic safety.Close collaborations with the industry will enable HQP to gain both theoretical knowledge and practical experience and make them well qualified for advanced work placements.

地震是最具破坏性的自然灾害之一。为了应对近几十年来发生的几次破坏性地震，核工业正在认真研究现有的核电站地震风险评估方法。在现有的地震风险分析方法中，人们认识到了一些不足之处。在核电站中，有大量与安全相关的结构、系统和部件(SSC)。确保安全关闭和防止地震期间发生事故的最有效方法是通过抗震设计和地震风险评估确保这些SSC有足够的安全裕度。我的研究计划的长期目标是为核电站的概率地震风险分析和设计建立一个系统的框架。通过与核工业伙伴的持续合作，拟议的研究将令人满意地解决困扰地震工程和核工业数十年的两个重要问题：(1)生成无漂移、一致和完美谱兼容的三向时程；(2)考虑土-结构相互作用的柔性基础楼板反应谱(FRS)的直接生成方法。时程分析已广泛应用于实际中，例如，在非线性动力分析和多点支撑体系的分析中。利用特征函数展开和影响矩阵的方法，该研究将开发出一种高效且易于使用的算法来生成无漂移、一致且与谱完全兼容的三向地震动时程。所开发的算法和软件在地震工程中具有重要的实用价值，准确确定作为SSCS的地震输入的FRS是地震分析中最关键的任务之一。过于保守的FRS增加了成本，而非保守的FRS则损害了安全性。我的研究小组最近开发了一种直接光谱到光谱的方法，用于产生准确和高效的红外光谱。该方法适用于固定基础结构模型的FRS计算，并已成功应用于Candu Energy Inc.的一个商业项目。在拟议的研究中，直接法将扩展到考虑柔性基础和SSI。土壤性质的不确定性对SSI分析的影响将被准确地解决，并将开发一种完整的概率方法来模拟不确定性。这项研究将提供先进的方法和现代工具来评估翻新核电站现有SSC的地震裕度和风险，并在新的核电站中设计新的SSC以确保地震安全。与业界的密切合作将使HQP获得理论知识和实践经验，使他们能够很好地胜任高级工作安排。