Behaviour and design procedures for transmission towers under high intensity wind loads

高强度风荷载下输电塔的性能和设计程序

• 批准号: 194602-2010
• 负责人: ElDamatty, Ashraf
• 金额: $ 1.75万
• 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: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=523239
• 关键词: Behaviour; design; procedures; transmission; towers

High Intensity Winds (HIW), which include tornadoes and downbursts, are responsible for more than 80% of all the world's weather-related transmission line failures. Despite this fact, the codes of design for transmission lines are based on a conventional wind profile associated with large scale events. HIW have different profiles, which impact the distribution of wind loads over the towers and lines. A research program was conducted at UWO in collaboration with Manitoba Hydro (MH) and other utility companies. A numerical tool was developed to predict the response of transmission lines to HIW. It incorporates wind field simulating HIW obtained from a computational fluid dynamic analysis. Various components of this numerical model were validated separately. The study revealed that structure members located at various regions of a tower can have specific critical HIW characteristics, defined by the size and location of the event, that lead to maximum forces in these members. In the current study, continuous monitoring for the wind velocity and the vibrations of a transmission line system will be conducted. The results will provide more insight about the HIW fields and the response of the towers to those events. They will also be used to validate the entire numerical model. A number of transmission line systems, having various structural configurations, will be numerically modeled. The results will be used to propose a set of design load cases simulating an envelope for the critical HIW cases for various structural systems. An accurate failure model for various components of the transmission lines will be incorporated into the numerical model. This will allow studying the progressive collapse of the towers during HIW. This extended model, together with available climate data for HIW, will lead to the development of a design procedure that will include recommended wind speeds and design load cases. The design procedure will ensure that transmission lines remain undamaged during moderate HIW, while preventing a total collapse during strong HIW. This will help in mitigating the economical and social losses associated with the failures of transmission lines during HIW. Three Ph.D. and two M.Sc. students will be involved in this proposal.

高强度风（HIW），包括龙卷风和下击暴流，是造成世界上80%以上与天气有关的输电线路故障的原因。尽管如此，输电线路的设计规范是基于与大规模事件相关的传统风廓线。HIW具有不同的轮廓，这影响风荷载在塔架和线路上的分布。一项研究计划是在UWO与马尼托巴水电（MH）和其他公用事业公司合作进行的。开发了一种数值计算工具，用于预测输电线路对高强度波的响应。它包括风场模拟HIW从计算流体动力学分析。该数值模型的各个组成部分分别进行了验证。该研究表明，位于塔架不同区域的结构构件可能具有特定的临界HIW特征，这些特征由事件的大小和位置定义，导致这些构件中的最大力。在目前的研究中，将对风速和输电线系统的振动进行连续监测。 结果将提供更多关于HIW场和塔对这些事件的响应的见解。它们还将用于验证整个数值模型。一些传输线系统，具有不同的结构配置，将进行数值模拟。结果将用于提出一组设计荷载工况，模拟各种结构系统的临界HIW工况的包络线。一个准确的故障模型的传输线的各种组件将被纳入到数值模型。这将允许研究HIW期间塔的连续倒塌。该扩展模型与HIW的可用气候数据一起，将导致设计程序的开发，该程序将包括推荐的风速和设计荷载工况。设计程序将确保输电线路在中等HIW期间保持不受损坏，同时防止在强HIW期间完全崩溃。这将有助于减轻HIW期间与输电线路故障相关的经济和社会损失。三个博士两名硕士生将参与这项提案。