Collaborative Research: Modeling Hurricane-Induced Windborne Debris to Reduce Damage in Urban Communities

许多飓风后的调查报告说，位于城市地区的建筑物的玻璃覆面和外墙遭到了过度和昂贵的破坏。由此造成的内部雨水破坏和建筑功能长期丧失，可能对城市社区内和周围的社会经济系统产生严重的不利影响。过去对大风事件后的损害的研究已经认识到，80%以上的玻璃破碎是由风吹来的碎片(如碎玻璃碎片和邻近建筑物的材料)造成的，而不是直接的风压加载玻璃。适当的经济高效的解决方案首先要全面了解该漏洞。然而，密集建筑物周围高度湍动的城市风场使风载垃圾的传输和碰撞的准确建模和预测变得非常复杂。该项目将通过1)美国国家科学基金会支持的佛罗里达大学自然危害工程研究基础设施(NHERI)边界层风洞的新风洞测试计划，2)数据驱动的计算机模拟方法，以及3)基于物理的碎片来源、飞行和撞击模型，来模拟碎片对集群城市建筑的潜在物理过程。其结果将是一个新的碎片损害脆弱性评估平台，使风险一致的努力，以减少城市建筑围护结构的风损害。在这项研究的同时，将开发一个交互式增强现实工具，以可视化建筑物群周围的三维流动和碎片飞行轨迹。这将是一个暑期项目的核心，该项目旨在让高中生从代表不足的群体中学习工程学，并鼓励STEM职业道路。该项目产生的数据将被存档，并在国家医疗保险研究所数据仓库(https://www.DesignSafe-ci.org).)公开可用这项研究项目将通过对复杂的城市水流特征和建筑物群周围的碎片飞行轨迹进行显式建模，促进对城市风中碎片运输基本物理的理解和建模。这将直接解决目前在城市风载碎片灾害机制建模方面存在的知识差距。新的风洞实验技术将使项目组能够捕获三维城市风场和碎片轨迹，从而产生首个此类数据，用于开发数据驱动的风场模型和系统验证复杂城市风的数值轨迹模型。通过主动学习，风洞实验和数据驱动建模之间的一种新的集成将被开发出来，以有效地预测风洞数据不可用的通用建筑群的风场。将开发一种概率不确定性量化程序，通过严格传播来自碎片源、城市风场、碎片轨迹和撞击模型的不确定性来评估风载碎片损害风险。该项目的成果将能够评估和改善城市建筑群的飓风复原力，这是社区复原力规划中存在的一个重大研究空白。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Numerous post-hurricane investigations have reported excessive and costly damage to glass cladding and façades of buildings located in urban areas. The resulting interior rainwater damage and extended periods of loss in building functionality can have substantial adverse effects on the socio-economic systems within and surrounding urban communities. Past studies of damage after high wind events have recognized that more than 80% of glass breakage was caused by windborne debris (such as broken glass pieces and materials from neighboring buildings) rather than direct wind pressure loading the glass. Appropriate cost-effective solutions begin with a comprehensive understanding of this vulnerability. However, the highly turbulent urban wind field around densely clustered buildings significantly complicates the accurate modeling and prediction of windborne debris transport and impact. This project will model the underlying physical process of the debris impact on clustered urban buildings through a combination of 1) a novel wind tunnel test program at the NSF-supported Natural Hazards Engineering Research Infrastructure (NHERI) boundary layer wind tunnel at the University of Florida, 2) data-driven computer simulation approaches, and 3) physics-based models of debris origin, flight, and impact. The result will be a new debris damage vulnerability assessment platform that enables risk-consistent efforts to reduce wind damage to the urban building envelope. Concurrent with the research, an interactive augmented reality tool will be developed to visualize the three-dimensional flow around building clusters and debris flight trajectory. This will be the centerpiece of a summer program that exposes high school students from underrepresented groups to engineering and encourages STEM career paths. Data generated by this project will be archived and made publicly available in the NHERI Data Depot (https://www.DesignSafe-ci.org). This research project will advance the understanding and modeling of the underlying physics of debris transport in urban winds through explicit modeling of complex urban flow features and debris flight trajectories around building clusters. This will directly address the current knowledge gap present in modeling of urban windborne debris hazard mechanisms. New wind tunnel experimental techniques will enable the project team to capture three-dimensional urban wind fields and debris trajectories, resulting in first-of-its-kind data necessary for developing the data-driven wind field models and systematically validating numerical trajectory models for complex urban winds. A novel integration between the wind tunnel experiments and data-driven modeling will be developed through active learning to efficiently predict wind fields for generic building clusters where wind tunnel data is not available. A probabilistic uncertainty quantification procedure will be developed to evaluate windborne debris damage risk through rigorous propagation of uncertainties from debris sources, urban wind fields, debris trajectory, and impact models. The outcome of this project will enable assessment and improvement of hurricane resilience for urban building clusters, which is a significant research gap present in community resilience planning.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.