LCE: Reliability-Based Simulation for Performance-Based Design

该工程科学建模和仿真为基础的生命周期工程（LCE）赠款提供资金，用于开发先进的计算工具，以预测复杂结构系统对极端自然现象危害的反应，分析不确定性，并管理风险。 将开发时变结构可靠性方法，以提供不确定环境模型、结构系统物理模型及其性能要求之间的接口。 数据库和其他信息，从实验或现场数据，模型模拟和专家意见将被纳入使用计算贝叶斯框架。 将研究在不确定性下使用确定包含-排除界限的锐化方法来评估结构性能的高效技术。 这些方法将使用当前重要的测试问题进行演示：建筑结构系统在强地震随机地面运动作用下的易损性建模。如果成功，本研究开发的决策工具将提供复杂民用基础设施在其50至100年的使用寿命期间的真实情况，这可用作新的基于性能的设计范例和管理极端自然灾害造成的设施风险的基础。 在最近对地震和飓风期间建筑物性能的灾后评估中发现，目前的设计做法无法防止非危及生命形式的结构损坏和功能中断，这可能导致直接经济和机会成本接近或超过结构成本。 公众要求工程解决方案具有更可预测和更可控的性能、更高的耐用性和更低的生命周期成本。 在适当的民用基础设施试验台问题上展示先进的决策理论技术，将加速改进和加强建筑技术和结构设计方面的竞争，最大限度地减少原型试验的需要，并降低自然灾害造成的死亡、受伤和财产损失的风险。

This Engineering Sciences for Modeling and Simulation-Based Life-Cycle Engineering (LCE) grant provides funding for the development of advanced computational tools to forecast the response of complex structural systems to extreme natural phenomena hazards, to analyze uncertainties, and to manage risk. Time-dependent structural reliability methods will be developed to provide the interfaces between models of the uncertain environment, physical models of the structural system, and its performance requirements. Databases and other information from experiment or field data, model simulation, and expert opinion will be incorporated using a computational Bayes framework. Highly efficient techniques for evaluating structural performance under uncertainty using sharpened methods for determining inclusion-exclusion bounds, will be investigated. The methods will be demonstrated using a testbed problem of significant current interest: fragility modeling of building structural systems subjected to severe earthquake stochastic ground motions.If successful, the decision tools developed in this research will provide a living picture of a complex civil infrastructure facility during its service life of 50 to 100 years, which could be used as a basis for the new performance-based design paradigm and for managing facility risk due to extreme natural hazards. In recent post-disaster assessments of building performance during earthquakes and hurricanes, it has been found that current design practices do not prevent non-life-threatening forms of structural damage and functional disruptions that may lead to direct economic and opportunity costs that approach or exceed the cost of the structure. The public is demanding engineering solutions with more predictable and controlled performance, greater durability, and lower life-cycle costs. A demonstration of advanced decision-theoretic technologies on an appropriate civil infrastructure testbed problem would accelerate improvements and enhance competition in building technologies and in structural design, minimize the need for prototype testing, and lower the risk of death, injury and property damage from natural hazards.