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.

主要研究者：Rajagopalan Balaji;科罗拉多大学面对飓风，结构系统可靠性的评估和预测对我们国家来说非常重要。一些公共和私营规划和灾害管理机构需要这种资料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，以评估和设定保险费水平。结构风险和可靠性模型存在于私营部门，但它们不是公共领域，而且往往是临时性的。此外，这些模型在评估结构可靠性时，不考虑对飓风频率、强度及其相关特征（如风、降水和洪水）的实际可能性估计。因此，有一个真实的需要开发一个综合框架，具有现实的飓风轨迹模拟模型与结构风险/可靠性模型相结合，以产生静态（长期）和动态（时变）的结构风险，并能够根据其可靠性对结构进行分类。 研究目的由于需要一个全面和综合的框架作为动机，拟议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任何所需位置的事件发生概率（事件由风速和降水的阈值连续性定义，因为风速是结构上的关键载荷因素）。还可以根据气候指标估计这些概率[例如，厄尔尼诺南方涛动、北大西洋涛动等。2. 为了开发不同类别结构的结构载荷概率（例如， 木材、砖石、混凝土等）基于. event。概率是从上面发展起来的。3.建立以荷载概率为条件的结构可靠性估计（包括静态和时变）。这些结果将有助于我们在飓风路径模拟模型中实施这一框架。本提案试图为飓风下的结构风险/可靠性评估制定跨学科框架。 该方法的独特之处在于它汇集了以下方面的知识：（a）大西洋飓风的变异性（包括飓风的数量和路径）;（B）估计相关组成部分（降水、风、洪水等）的概率;（b）估计飓风的强度和强度。使用非参数函数估计技术，（c）概率结构载荷估计，以及（d）贝叶斯技术进行结构风险/可靠性评估，以开发长期和时变风险估计。这种对实际问题的独特和综合的方法是这项建议的主要智力价值。更广泛的影响本研究的结果将大大有助于开发应用这个框架结合随机飓风路径模拟模型，为整个美国海岸和不同的结构群。这也将补充联邦应急管理局的HAZUS倡议，以加强国家在自然灾害下的风险评估能力。这些成果将极大地有助于它们对民用基础设施评估领域的知识基础和知识增长以及减少飓风造成的风险作出贡献。