Quality control and fatigue design of friction stir welded joints in aluminum bridge decks

铝桥面搅拌摩擦焊接头的质量控制和疲劳设计

• 批准号: 494843-2016
• 负责人: Walbridge, Scott
• 金额: $ 3.1万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=618111
• 关键词: Quality; control; fatigue; design; friction

Highway authorities in North America are currently faced with significant and pressing bridge maintenance costs. A recent industry report on aluminum use in bridges found light weight decks for new bridges and rehabilitation projects to be an application area with particular promise. A subsequent economic study concluded that: 1) bridge decks are an application where aluminum clearly has a potential for market growth, and 2) friction stir welding (FSW) represents a transformative technology, which could have a significant influence on the durability and economics of aluminum bridge decks. A design code for structural FSW joints does not yet exist in Canada. Existing international codes (e.g. ISO, AWS) include quality control provisions based on "best practice", which have not yet been related to structural performance. This project will be be performed collaboratively by researchers at the University of Waterloo (UW) and Université du Québec à Chicoutimi (UQAC) with the goal of developing improved, "performance-based" code provisions for the quality control (QC) and fatigue design of FSW joints in aluminum bridge decks. To achieve this goal, the following tasks will be performed: 1) specimen preparation and metallurgical analysis; 2) fatigue testing of FSW specimens; 3) statistical and fracture mechanics analysis of FSW test results; and 4) development of improved guidelines for QC and fatigue design of FSW bridge deck joints. A particularly novel aspect of the project will be the plan to fatigue test and analyze welds with varying levels of quality (i.e. various defect types with varying degrees of severity). This project will make a significant contribution to the current state-of-knowledge, which will move the Canadian industry and researchers working on FSW to the leading edge of this field, through the new knowledge acquired and the transformation of this knowledge into design recommendations.

北美的公路当局目前面临着巨大而紧迫的桥梁维修费用。最近一份关于铝在桥梁中的应用的行业报告发现，用于新建桥梁和修复项目的轻型桥面是一个特别有前途的应用领域。随后的一项经济研究得出结论：1)桥面板是铝明显具有市场增长潜力的应用领域，2)搅拌摩擦焊（FSW）代表了一种变革性技术，可能对铝制桥面板的耐久性和经济性产生重大影响。加拿大目前还没有关于结构摩擦焊接头的设计规范。现有的国际规范（例如ISO， AWS）包括基于“最佳实践”的质量控制规定，这些规定尚未与结构性能相关。该项目将由滑铁卢大学（UW）和奇库蒂米大学（UQAC）的研究人员合作进行，目标是为铝桥面FSW接头的质量控制（QC）和疲劳设计制定改进的“基于性能”的规范规定。为了实现这一目标，将执行以下任务：1)试样制备和冶金分析；2) FSW试件疲劳试验；3) FSW试验结果统计与断裂力学分析；4)制定改进的FSW桥面接缝质量控制和疲劳设计指南。该项目的一个特别新颖的方面将是对不同质量水平（即不同严重程度的各种缺陷类型）的焊接进行疲劳测试和分析的计划。该项目将对当前的知识状态做出重大贡献，通过获得的新知识和将这些知识转化为设计建议，将推动加拿大工业和FSW研究人员走在该领域的前沿。