Reducing Weld Sizes in Circular Hollow Section Connections

减小圆形空心截面连接的焊缝尺寸

• 批准号: RGPIN-2019-04093
• 负责人: Tousignant, Kyle
• 金额: $ 2.26万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=714548
• 关键词: Reducing; Weld; Sizes; Circular; Hollow

In Canada, the cost of steel fabrication labour (for connections) can account for 60% of the cost of a steel structure. This % continues to rise. It is therefore increasingly important for engineers to reduce labour required to make connections to keep Canada's steel industry competitive. For welded tubular structures, this is a present challenge due to a lack of design guidance on welding to circular hollow sections (CHS). This is because the behaviour of welds in such joints, with respect to eccentric loading and non-uniform loading, is not well-understood. In lieu of guidance, designers “oversize” welds to prevent failure. This is usually a safe approach, but it leads to a lot of unnecessary labour for joint preparation and welding. The long-term objective of this research program is to develop a better (more economical, yet still safe) design approach for welds in CHS connections. First, this research will identify the effect of eccentric loading on the strength of two types of welds: fillet welds and partial joint penetration (PJP) groove welds. Lab tests will be conducted on weld-critical eccentrically tension-loaded cruciform connections (ETLCCs) with one-sided welds (to mimic the situation in CHS connections). The effect of weld type, root penetration, eccentricity (magnitude and direction), and plate-element thickness on weld strength will be identified. Then, post-rupture tests (e.g. Vickers hardness) will be used to characterize the local material properties of the ETLCCs near the welds (i.e. the properties of the filler metal, base metal, and heat-affected zone). These properties will subsequently be used in finite element (FE) models of the ETLCCs to study approaches to simulating weld fracture. A standardized approach for extending large-scale fracture-critical connection test results (using FE methods) will be developed. Lastly, with this new approach, FE models of CHS connections (with weld fracture) will be developed to determine the combined effect of non-uniform loading and eccentric loading on the weld strength. Large-scale, fracture-critical lab tests will be conducted, in parallel, to verify these models. This research will generate new knowledge and much-needed design guidance on welding to CHS that will help engineers reduce weld sizes and associated labour costs. It will also support the training of 2 doctoral, 3 master's and 2 undergraduate highly qualified personnel.

在加拿大，钢铁的成本（用于连接）可以占ATEEL结构的60％，这对于劳动行业的竞争力很重要。关节装载不及格，以代替指导，设计师，“预防。仍然安全）CHS连接中焊缝的设计方法。 首先，两种类型的焊缝的偏心载荷：圆角焊缝和部分连接p）凹槽焊缝将对实验室测试进行。连接）。碱金属和热影响区）随后将使用ETLCC的有限元素（Fe）模型来研究焊接骨折的结果（使用FE方法）。方法将开发CHS连接骨折的Fe模型），以确定不均匀的载荷和偏心载荷对焊缝强度的合并效果。 这项研究将基因并急需向CHS THELP工程师进行焊接的指导，降低了焊接大小相关的滥用成本。