Performance-Based Design of Transmission Line Structures Under Tornadoes and Downbursts

龙卷风和下击暴流下输电线路结构的基于性能的设计

• 批准号: RGPIN-2016-04771
• 负责人: ElDamatty, Ashraf
• 金额: $ 3.64万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=649985
• 关键词: Performance; Based; Design; Transmission; Line

Downbursts and tornadoes belong to a category of storms that are referred to as High Intensity Winds (HIW). The proposed research focuses on the effect of these extreme events on transmission line (TL) structures. Failure incidents of those structures during HIW events have been observed on an annual basis in Canada and amongst other countries, resulting in huge economic losses. Western has consistently taken the lead in research related to the effect of wind on structures. Its research capabilities have been augmented by the establishment of the WindEEE dome, a $30M facility representing the first chamber in the world for testing structures under large scale HIW. The HIW fields consist of a mean and a turbulent component, which are both dependent on whether the site terrain is open, suburban or urban. In his previous DG, the applicant focused on the effect of the mean component of the HIW fields on TLs in the case of open terrain. With the availability of HIW field data from the WindEEE, the research will be taken to a higher level. Numerical simulations will be conducted for TLs using HIW fields corresponding to different terrains, while varying the location of the event. Critical locations leading to peak forces in the tower members will be identified. The analyses will be conducted considering the dynamic effects resulting from turbulence. The outcome will take the form of load cases simulating the critical effects of the mean component of HIWs for various terrain conditions, together with gust response factors magnifying these loads to account for dynamic effects. When a transmission tower collapses, the de-attachment of the connected conductors leads to the creation of unbalanced longitudinal forces acting on subsequent towers causing a chain of tower failures. A novel nonlinear numerical model will be developed to simulate the progressive collapse of an entire line system, which will be validated experimentally through tests conducted at WindEEE. This experimental program will take wind testing to new horizons for failure investigation, benefiting from the availability of a large scale wind testing facility. Since a TL extends for hundreds of kilometers, it could be very expensive and impractical to design all the towers of a line to remain undamaged under extreme HIW events. A performance-based design procedure will be developed as described in this proposal. The desired performance criteria will involve the minimization of the effect and the duration of the interruption of electricity due to the failure of a portion of the line as well as the containment of such a failure. The research will lead to finding a sustainable solution to a worldwide problem, will set up a framework for a performance-based design of structures under wind loading, and will provide training for 6 graduate students in state-of-the–art numerical and experimental techniques, which will address a very practical and pressing problem.

爆炸和龙卷风属于被称为高强度风（HIW）的风暴类别。拟议的研究重点是这些极端事件对传输线（TL）结构的影响。在加拿大和其他国家 /地区，在HIW事件期间，这些结构发生的故障事件已每年观察到，造成了巨大的经济损失。西方一直在与风对结构的影响有关的研究领导。 Windeee Dome的建立增强了它的研究能力，Windeee Dome是3000万美元的设施，代表了世界上第一个用于大规模HIW下测试结构的房间。 HIW字段由平均值和动荡的组成部分组成，它们都取决于场地的地形是开放的，郊区还是城市。在他以前的DG中，适用于HIW场的平均成分对TLS的效果。随着Wineee的HIW现场数据的可用性，该研究将被带到更高的水平。将使用与不同地形相对应的HIW字段为TLS进行数值模拟，同时改变事件的位置。将确定导致塔式成员峰值力量的关键位置。考虑到湍流产生的动态影响，将进行分析。结果将采用负载案例的形式，模拟HIW在各种地形条件下的含义成分的关键效应，以及阵风响应因素放大这些负载以考虑动态效应。当变速箱塔倒塌时，连接导体的解开会导致产生不平衡的纵向力，该纵向作用于随后的塔楼，导致塔链链破坏。将开发一个新型的非线性数值模型来模拟整个线系统的进行性崩溃，该模型将通过Windeee进行的测试对实验进行验证。该实验计划将使大规模风测试设施的可用性受益于新的视野进行故障调查。由于TL延伸了数百公里，因此在极端的HIW事件下，设计所有线路以保持不衰老可能是非常昂贵且不切实际的。基于绩效的设计程序将如本提案中所述开发。所需的性能标准将涉及由于一部分线的故障以及这种故障的遏制，效果的最小化和电力中断的持续时间。这项研究将导致为全球问题找到可持续的解决方案，将建立一个基于绩效的结构设计的框架，并将为在最先进的数值和实验技术中为6名研究生提供培训，这将解决一个非常实用和紧迫的问题。