Experimentally Validated Stochastic Numerical Framework to Generate Multi-Dimensional Fragilities for Hurricane Resilience Enhancement of Transmission Systems

美国的电力传输基础设施，特别是沿海地区的电力传输基础设施，面临着飓风的巨大风险。考虑到输电电网的巨大规模，升级整个基础设施以达到可接受的飓风性能水平的成本将非常高。这项研究的目的是调查一个框架，以可靠地识别脆弱的输电线路系统，并提供具有成本效益的改造解决方案，以减少它们在飓风期间受损和功能丧失的可能性，以及它们在飓风发生后的恢复时间。为此，本项目将使用经过实验验证的数值模型来开发输电铁塔-线路系统的多维脆弱性模型。这将能够表征各种重要因素对这些系统的风力性能的影响。这项研究的结果将有助于最大限度地减少因停电造成的关键基础设施和设施丧失功能而造成的社会破坏。该项目将积极与利益攸关方合作，促进技术转让和实施新的传动系统设计和改造解决方案。这些研究成果将被整合到俄亥俄州立大学和佛罗里达国际大学的课程中。此外，未被充分代表的本科生和K-8级学生将接受基础设施系统研究方面的培训，以培养下一代工程师，以增强社区的飓风抵御能力。这项研究将产生一个经过实验验证的最先进的随机数值框架，以生成用于增强传输系统飓风抵御能力的多维脆弱性模型。这项研究将涉及在FIU国家科学基金资助的自然灾害工程研究基础设施风墙(WOW)实验设施中进行的一系列关于多跨输电系统风响应的气动弹性风洞研究。这些新颖的实验数据，以及高保真的塔-导体-绝缘子-地基系统的三维非线性有限元模型，将为这些系统各种复杂的风致行为提供新的和关键的见解。WOW测试还将能够表征相邻跨度的动态边界效应。基于验证的数值模型的多维脆弱面将提供输电塔线单元的部件级和系统级的结构和功能失效概率。生成的可靠性模型与恢复模型相结合，将被整合到优化框架中，以提供基于灾害和环境因素的优化设计和改造解决方案，这将促进输电系统对飓风危害的优化管理，以增强其对极端事件的应变能力。

The electric power transmission infrastructure in the United States, especially in coastal areas, faces substantial risk from hurricanes. Considering the significant size of the transmission grid, the cost of upgrading the entire infrastructure to achieve acceptable performance levels against hurricanes would be extremely high. The objective of this research is to investigate a framework to reliably identify vulnerable transmission line systems and provide cost-effective retrofit solutions to reduce their likelihood of damage and loss of functionality during hurricanes and their recovery time following the event. For this purpose, this project will develop multi-dimensional fragility models for transmission tower-line systems using experimentally validated numerical models. This will enable characterization of the effects of various significant factors on the wind performance of these systems. Outcomes of this research will aid in minimizing societal disruptions due to loss of functioning of critical infrastructure and facilities caused by power outages. The project will actively engage stakeholders to facilitate technology transfer and implementation of novel design and retrofit solutions for transmission systems. The research findings will be integrated into courses at Ohio State University and Florida International University (FIU). In addition, underrepresented undergraduate and K-8 students will be trained in research on infrastructure systems to prepare the next generation of engineers to enhance the hurricane resilience of communities.The research will produce a state-of-the-art experimentally validated stochastic numerical framework to generate multi-dimensional fragility models for hurricane resilience enhancement of transmission systems. The research will involve a series of aeroelastic wind tunnel studies on the wind response of multi-span transmission systems at the National Science Foundation-supported Natural Hazards Engineering Research Infrastructure Wall of Wind (WOW) Experimental Facility at FIU. These novel sets of experimental data, together with high-fidelity three-dimensional nonlinear finite element models of tower-conductor-insulator-foundation systems, will provide new and critical insights into various complex wind-induced behaviors of these systems. The WOW tests will also enable characterization of dynamic boundary effects from neighboring spans. The multi-dimensional fragility surfaces, based on validated numerical models, will provide component- and system-level structural and functional failure probabilities for units of transmission tower-lines. The generated reliability models, combined with recovery models, will be integrated into optimization frameworks to provide optimal design and retrofit solutions based on hazard and environmental factors, which will facilitate optimal management of transmission systems against hurricane hazards to enhance their resilience in response to extreme events.