权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Benchmark Study of Tornado Wind Loading on Low-Rise Buildings with Consideration of Internal Pressure

考虑内压的低层建筑龙卷风风荷载基准研究

基本信息

批准号：
1663363
负责人：
Delong Zuo
金额：
$ 35万
依托单位：
Texas Tech University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2017
资助国家：
美国
起止时间：
2017-05-01 至 2022-04-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1663363&HistoricalAwards=false
关键词：
Benchmark Study Tornado Wind Loading

项目摘要

Tornadoes are historically among the most devastating natural hazards in the United States, as observed by the damage and fatalities during recent major tornadoes, including the Joplin, Missouri and Tuscaloosa-Birmingham, Alabama tornadoes in 2011, the Moore, Oklahoma tornado in 2013, and the Dallas, Texas area tornado in 2015. As post-tornado disaster surveys have repeatedly revealed, tornado-induced losses and fatalities are often due to damage to low-rise buildings. A critical factor contributing to such building damage is that many low-rise buildings are designed only for winds that travel mostly along a straight line near the earth's surface, and not for the rotating tornado winds that are potentially more damaging, primarily due to inadequate understanding of tornadoes and tornado wind loading on structures. The goal of this research is to formulate computational models that comprehensively characterize rotating tornado wind loading and the impact of such wind loading on low-rise buildings. Such models can be used by engineers to conduct performance-based evaluation of low-rise buildings subjected to tornado hazard as a way to reduce damage and fatalities. To raise awareness of the impact of natural hazards, including tornadoes, on buildings and communities, this research will be integrated into education and outreach activities within existing programs at Texas Tech University (TTU), such as courses offered by TTU's National Wind Institute Wind Science and Engineering Ph.D. program and ongoing outreach activities, including a 4-H Mentoring Program, Science Camp, and Lubbock's Annual Severe Awareness Day. To achieve this research goal, this project will test models of low-rise buildings with two roof types in various types of tornadic vortices simulated in a large-scale tornado simulator at TTU and straight-line winds simulated in the NSF-supported Natural Hazards Engineering Research Infrastructure (NHERI) boundary layer wind tunnel at the University of Florida to provide two benchmark datasets. These two datasets will be used to quantify the differences between the loadings by tornado and boundary-layer-type straight-line winds. The focus will be placed on the effects of building internal pressure and the nonstationary and non-Gaussian nature of tornado loading introduced by the translation of spatially varying wind speed and static pressure deficit in tornado vortices. On this basis, an innovative approach based on discrete wavelet transform and Gaussian filtering will be used to characterize, model, and simulate nonstationary, dynamic tornado wind loading on low-rise buildings to enable probabilistic evaluation of the loading effects. Project data will be made available in the NHERI Data Depot at https://www.designsafe-ci.org/.

从历史上看，龙卷风是美国最具破坏性的自然灾害之一，从最近几次主要龙卷风的破坏和死亡情况来看，这些龙卷风包括2011年的密苏里州乔普林和阿拉巴马州的塔斯卡卢萨-伯明翰龙卷风，2013年的俄克拉何马州摩尔龙卷风，以及2015年的德克萨斯州达拉斯龙卷风。正如龙卷风后灾害调查一再揭示的那样，龙卷风造成的损失和死亡往往是由于低层建筑的损坏。造成这种建筑损坏的一个关键因素是，许多低层建筑的设计只针对主要沿地表附近的直线移动的风，而不是旋转的龙卷风，后者可能更具破坏性，主要是因为对龙卷风和龙卷风对建筑物的加载缺乏了解。这项研究的目的是建立计算模型，全面描述旋转龙卷风荷载以及这种风荷载对低层建筑的影响。工程师可以使用这种模型对遭受龙卷风危害的低层建筑进行基于性能的评估，以此来减少损失和死亡。为了提高人们对包括龙卷风在内的自然灾害对建筑物和社区影响的认识，这项研究将被整合到德克萨斯理工大学(TTU)现有项目的教育和推广活动中，例如德克萨斯理工大学(TTU)国家风研究所风科学与工程博士项目提供的课程和正在进行的推广活动，包括4-H辅导计划、科学营和Lubock的年度严重意识日。为了实现这一研究目标，该项目将测试TTU大型龙卷风模拟器中模拟的不同类型龙卷风和佛罗里达大学NSF支持的自然危害工程研究基础设施(NHERI)边界层风洞中模拟的直线风的两种屋顶类型的低层建筑模型，以提供两个基准数据集。这两个数据集将被用来量化龙卷风和边界层型直线风负荷之间的差异。重点将放在建筑物内部压力的影响，以及龙卷风负荷的非平稳和非高斯性质，这是通过龙卷风涡旋中空间变化的风速和静压差的平移而引入的。在此基础上，采用一种基于离散小波变换和高斯滤波的创新方法，对低层建筑上的非平稳、动态龙卷风荷载进行表征、建模和模拟，以实现对荷载效应的概率评估。项目数据将在位于https://www.designsafe-ci.org/.的NHERI数据仓库中提供