Development of stability design guidelines for modern I-shaped welded steel girders in Canada

加拿大现代工字形焊接钢梁稳定性设计指南的制定

• 批准号: 519937-2017
• 负责人: Imanpour, Ali
• 金额: $ 0.95万
• 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: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=675351
• 关键词: Development; stability; design; guidelines; modern

Many building structures and bridges in North America are built with welded steel girders to resist gravityloads. The design of such girders is typically governed by their stability; however, various parameters canaffect their stability response, including cross-sectional properties, end and loading conditions, built-in stressesand initial geometric imperfections. Current Canadian design standards are supported by studies that do notnecessarily represent the design and fabrication practice of modern girders. The validity of past experimentalstudies and corresponding numerical simulations is questionable because of their reliance on small-scale testspecimens and fabrication processes that are no longer practiced. Additionally, few studies include detailedquantification of the influential parameters. To better understand stability of modern welded steel girders,designers need improved guidelines based on data that reflect the actual behaviour of the member under designloads. Our research project focuses on four key objectives: 1) to thoroughly measure the amplitude and patternof residual stresses that develop in the course of contemporary manufacturing and welding processes; 2) toevaluate the stability requirements for welded girders in steel bridges and buildings in light of the effect ofresidual stresses; 3) to evaluate current Canadian stability design requirements for I-shaped welded steelgirders; and 4) to generate design recommendations for changes to Canadian standards for stabilityrequirements in steel construction and bridge design. To achieve these aims, the research team will performfull-scale lab experiments and employ numerical modelling. We will also provide improved design tools tostructural engineers for their daily work, resulting in safer structures and reduced construction costs.

北美的许多建筑结构和桥梁都是用焊接钢梁建造的，以抵抗重力荷载。这种梁的设计通常由其稳定性决定;然而，各种参数会影响其稳定性响应，包括横截面特性、端部和载荷条件、内置应力和初始几何缺陷。现行的加拿大设计标准得到了研究的支持，这些研究不一定代表现代大梁的设计和制造实践。过去的实验研究和相应的数值模拟的有效性是值得怀疑的，因为它们依赖于小规模的测试样本和不再实践的制造工艺。此外，很少有研究包括详细的量化的影响参数。为了更好地了解现代焊接钢梁的稳定性，设计人员需要根据反映设计荷载下构件实际行为的数据改进指南。我们的研究项目集中在四个关键目标：1）彻底测量当代制造和焊接过程中产生的残余应力的幅度和模式; 2）根据残余应力的影响评估钢桥和建筑物中焊接钢梁的稳定性要求; 3）评估加拿大目前对I形焊接钢梁的稳定性设计要求;以及4）为改变加拿大钢结构和桥梁设计的稳定性要求标准提供设计建议。为了实现这些目标，研究小组将进行全面的实验室实验，并采用数值模拟。我们还将为结构工程师的日常工作提供改进的设计工具，从而使结构更安全，并降低建筑成本。