SGER: A Feasibility Study of Estimation of Structural Systems Reliability Under Hurricane Hazard

SGER：飓风灾害下结构系统可靠性估算的可行性研究

• 批准号: 0335530
• 负责人: Rajagopalan Balaji
• 金额: $ 4万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-15 至 2004-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0335530&HistoricalAwards=false
• 关键词: SGER; Feasibility; Study; Estimation; Structural

PI: Rajagopalan Balaji; University of ColoradoThe assessment and prediction of structural system reliability in the face of hurricanes are of great interest to our nation. Several public and private planning and disaster management agencies need such information for developmental planning and disaster mitigation strategies. Also, insurance agencies are interested in the structural reliability estimates to evaluate and set premium levels. Models for structural risk and reliability exist in the private sector but they are not public domain, and often they are adhoc in nature. Furthermore, these models evaluate structural reliability in isolation of realistic likelihood estimates of hurricane frequencies, magnitudes and their associated characteristics (such as winds, precipitation and floods). Thus, there is a real need for the development of an integrative framework that has a realistic hurricane track simulation model coupled with a structural risk/reliability model, to generate static (long term) and dynamic (time varying) structural risks and also the capability to classify structures as per their reliability. Objectives of the study With the need for a comprehensive and integrated framework as the motivation, the aim of the proposed study is to demonstrate the feasibility of the integrative framework. To this end the objectives are: 1. Use the historical hurricane track data to compute probabilities of occurrences of .events at any desired location (events are defined by threshold exceedence of wind speed and precipitation, as wind speed are the key loading factors on structures). Also estimate these probabilities conditioned on climate indications [e.g., El-Nino Southern Oscillation, North Atlantic Oscillation etc.]. 2. To develop structural load probabilities on different class of structures (e.g., timber, masonary, concrete etc.) based on .event. probabilities developed from above. 3. To develop structural reliability estimates (both stationary and time varying) conditioned upon the load probabilities. These outcomes will help us in implementing this framework with hurricane track simulation models. Intellectual Merit This proposal attempts to develop cross-disciplinary framework for structural risk/reliability assessment in the face of hurricanes. The approach is unique in that it brings together the knowledge of (a) Atlantic hurricane variability (both in terms of the number of hurricanes and the tracks); (b) Estimating probabilities of associated components (precipitation, winds, flooding etc.) using nonparametric functional estimation techniques, (c) probabilistic structural load estimation, and (d) Bayesian techniques for structural risk/reliability assessment to develop long term and time varying risk estimates. This unique and integrative approach to a practical problem is the main intellectual merit of this proposal. Broader Impacts The outcomes from this study will significantly help in developing applying this framework in conjunction with a stochastic hurricane track simulation model, for the entire US coast and for different structural groups. This will also supplement the HAZUS initiative by FEMA for enhancing the nation.s risk assessment capabilities under natural hazards. These outcomes will be extremely helpful for their contributions to the knowledge base and intellectual growth in the area of civil infrastructure assessment as well as the reduction of risks induced by hurricanes.

PI：拉贾戈帕兰·巴拉吉；科罗拉多大学飓风面前结构系统可靠性的评估和预测引起了我们国家的极大兴趣。一些公共和私人规划和灾害管理机构需要此类信息来制定发展规划和减灾战略。此外，保险机构对结构可靠性估计感兴趣，以评估和设定保费水平。结构性风险和可靠性模型存在于私营部门，但它们不是公共领域，而且通常本质上是临时的。此外，这些模型在评估结构可靠性时，与飓风频率、强度及其相关特征（例如风、降水和洪水）的实际可能性估计无关。因此，确实需要开发一个综合框架，该框架具有真实的飓风路径模拟模型和结构风险/可靠性模型，以生成静态（长期）和动态（随时间变化）的结构风险以及能力根据结构的可靠性对结构进行分类。 研究目的 以建立全面综合框架的需求为动机，本研究的目的是证明综合框架的可行性。为此，目标是： 1. 使用历史飓风轨迹数据计算在任何所需位置发生事件的概率（事件是通过风速和降水的阈值超出来定义的，因为风速是结构上的关键载荷因素）。还要根据气候迹象[例如厄尔尼诺南方涛动、北大西洋涛动等]估计这些概率。 2. 基于.event 开发不同类型结构（例如木材、砖石、混凝土等）的结构荷载概率。从上面发展而来的概率。 3. 根据载荷概率制定结构可靠性估计（固定的和随时间变化的）。这些成果将帮助我们通过飓风路径模拟模型实施该框架。智力价值 该提案试图开发跨学科框架，用于飓风时的结构风险/可靠性评估。 该方法的独特之处在于它汇集了以下方面的知识：(a) 大西洋飓风的变化性（飓风数量和路径）； (b) 使用非参数函数估计技术估计相关组成部分（降水、风、洪水等）的概率，(c) 概率结构荷载估计，以及 (d) 用于结构风险/可靠性评估的贝叶斯技术，以开发长期和时变的技术风险估计。这种针对实际问题的独特而综合的方法是该提案的主要智力优点。更广泛的影响 这项研究的结果将极大地有助于将该框架与随机飓风路径模拟模型结合起来应用于整个美国海岸和不同的结构组。这也将补充 FEMA 的 HAZUS 倡议，以增强国家在自然灾害下的风险评估能力。这些成果对于他们对民用基础设施评估领域的知识库和智力增长以及减少飓风引起的风险的贡献非常有帮助。