Fire-Exposed Reinforced Concrete Frames: Structural Performance, Progressive Collapse Assessment and Retrofit Strategy

暴露在火灾中的钢筋混凝土框架：结构性能、渐进式倒塌评估和改造策略

• 批准号: RGPIN-2015-06058
• 负责人: Youssef, Maged
• 金额: $ 1.6万
• 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=669405
• 关键词: Fire; Exposed; Reinforced; Concrete; Frames

The collapse of the towers of the World Trade Center and the many documented fire-initiated structural failures raise grave concerns about public safety. The majority of Reinforced Concrete (RC) structures are designed using prescriptive fire design approaches that are based on structural tests of RC elements exposed to standard fires. However, they possess significant drawbacks including: undefined safety margin at the structure level, unknown resistance to progressive collapse and inapplicability to consider innovative cost-saving solutions demanded by the complex natural fire phenomena. They also fail to provide the needed guidance to evaluate and retrofit fire-damaged structures.***Design standards are being revolutionized by specifying acceptable performance criteria or design objectives to allow for engineering innovations. This revolution is causing a major shift in the balance of responsibility for fire safety between the architect and the structural engineer who needs to develop the necessary expertise and be equipped with the right analytical tools. These tools should expedite the design process allowing for the justification of the benefits associated with the additional engineering work.***The Applicant's research group has recently developed and validated simplified methods and tools to analyze and design RC frames exposed to standard fire. These provide researchers and engineers with the necessary means to understand the complicated structural behaviour under fire exposure, to design RC frames to satisfy specific safety objectives and to validate analysis results from commercial computer programs.***The proposed research will further develop the Applicant's methods and tools to make them suitable for cases of natural fire. Their use will allow for performance-based design of new structures and provide means to assess the safety of fire-damaged structures considering the potential of progressive collapse. Such assessment is essential to make critical decisions about the need for evacuation prior to retrofitting. Emergency response teams are in desperate need of such tools to continuously monitor the condition of fire-exposed structures to guarantee the safety of their personnel. The research will also provide tools to design retrofitting techniques for fire-damaged RC frames that guarantee public safety.***The proposed research will utilize the unique fire facility at Lambton College's Fire & Public Safety Centre of Excellence to expose RC elements to fire before testing them at Western's Structures Lab. Test results will lead to the development and validation of the above-mentioned tools. 6 HQPs and 25 Undergraduate students will experience unique testing procedures involving interaction with technicians from Western and Lambton, and will develop analytical skills that are much needed within the structural engineering profession in Canada and worldwide.**

世界贸易中心塔楼的崩溃以及许多有记录的火灾引发的结构性故障引起了人们对公共安全的严重关注。大多数钢筋混凝土（RC）结构是使用基于暴露于标准火灾的RC元素的结构测试的规范性火灾设计方法设计的。但是，它们具有重大的缺点，包括：在结构水平上不确定的安全余量，对渐进性崩溃的不明能力以及考虑复杂的自然火灾现象所需的创新成本解决方案的不适用性。他们还没有提供所需的指导来评估和改造造成的火灾损害结构。这场革命导致建筑师与需要发展必要专业知识并配备正确的分析工具的结构工程师之间的消防安全责任的平衡发生了重大转变。这些工具应加快设计过程，以允许与其他工程工作相关的收益。这些为研究人员和工程师提供了必要的手段，以了解暴露在火灾下的复杂结构行为，设计RC框架以满足特定的安全目标并验证商用计算机程序的分析结果。它们的使用将允许基于绩效的新结构设计，并为考虑性崩溃的潜力评估遭受火灾损坏的结构的安全性。这种评估对于在改造之前就需要撤离的需要做出关键决定至关重要。紧急响应小组迫切需要此类工具，以不断监视暴露的结构的状况，以确保其人员安全。这项研究还将提供为防火损伤的RC框架设计改造技术的工具，以保证公共安全。测试结果将导致上述工具的开发和验证。 6个HQP和25名本科生将体验涉及与西方和兰布顿技术人员互动的独特测试程序，并将发展加拿大和全球结构工程专业中急需的分析技能。**