Development of Design Guidelines for Steel Cantilever Beams in Canada

加拿大钢悬臂梁设计指南的制定

• 批准号: 543526-2019
• 负责人: Imanpour, Ali
• 金额: $ 2.68万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=720730
• 关键词: Development; Design; Guidelines; Steel; Cantilever

The roofs of many light single-storey steel buildings in North America that are large in plan area, such as supermarkets or big box stores, are built using the "Gerber system" to resist gravity loads. The Gerber system consists of cantilever girders that are supported atop the columns and interstitial drop-in girder segments along the column line in one direction, typically with open-web steel joists constituting the secondary framing in the perpendicular direction. This system tends to reduce girder sizes by taking advantage of the negative moment capacity of the girders at the column supports, while maintaining a cost similar to that of a simply-supported frame structure. The design of girders in such systems is often governed by their stability. The current Canadian standard for design of steel buildings, CSA S16, provides very limited information related to the Gerber system and it is therefore the responsibility of the structural engineer to develop a rational design method. Remarkably, and of concern to several leading industry experts, widely-used textbooks and guidelines may not adequately describe the behaviour and resistance of such system. This research project aims to develop design methods for steel Gerber systems and has four specific objectives: 1) to identify the influential parameters pertaining to the stability of cantilever girders; 2) to assess, by means of numerical simulations and a full-scale experimental program, the stability response of such girders; 3) to develop design methods for Gerber systems and other cantilevers, and propose stability design requirements within the framework of the Canadian steel design standard; and 4) to perform a thorough reliability analysis. The research team will perform full-scale laboratory experiments and employ advanced numerical modelling techniques to achieve the objectives of this project. The results will provide improved design tools to structural engineers for use in day-to-day practice, resulting in safer structures while reducing construction costs. The data obtained from the experimental test program proposed here will supplement existing studies to instill greater confidence in the validity of the design equations prescribed for cantilever girders.

北美许多轻型单层钢制建筑的屋顶在计划区域中很大，例如超市或大型商店，是使用“ Gerber系统”建造的，以抵抗重力负载。 Gerber系统由悬臂大梁组成，这些悬臂梁在圆柱和圆柱线沿圆柱线上沿一个方向支撑的圆柱段线组成，通常具有开放式网状钢托梁，构成了沿垂直方向的二级框架。该系统倾向于通过利用柱子支撑的梁的负矩容量来减少梁的大小，同时保持与简单支持的框架结构相似的成本。这种系统中大梁的设计通常受其稳定性的控制。 CSA S16的当前加拿大钢结构设计标准提供了与Gerber系统相关的非常有限的信息，因此，结构工程师有责任开发合理的设计方法。值得注意的是，对于几位领先的行业专家而言，广泛使用的教科书和准则可能无法充分描述这种系统的行为和抵抗力。该研究项目旨在开发钢制Gerber系统的设计方法，并具有四个特定的目标：1）确定与悬臂大梁稳定性有关的有影响力参数； 2）通过数值模拟和完整的实验程序评估此类梁的稳定性响应； 3）为Gerber系统和其他悬臂开发设计方法，并在加拿大钢制设计标准的框架内提出稳定设计要求； 4）进行彻底的可靠性分析。研究团队将执行全面的实验室实验，并采用先进的数值建模技术来实现该项目的目标。结果将为结构工程师提供改进的设计工具，以便在日常练习中使用，从而使结构更安全，同时降低建筑成本。从此处提出的实验测试计划中获得的数据将补充现有的研究，以灌输对悬臂梁规定的设计方程有效性的更大信心。