Development of constraint-based fracture mechanics methodologies for structural integrity assessments and fatigue life predictions

开发基于约束的断裂力学方法，用于结构完整性评估和疲劳寿命预测

• 批准号: 238232-2010
• 负责人: Wang, Xin
• 金额: $ 2.33万
• 依托单位: Carleton University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=524251
• 关键词: Development; constraint; based; fracture; mechanics

Safe operations of high performance engineering structures, such as those in nuclear pressure vessels, gas pipelines, offshore and aerospace industries, are of practical significance. To assure the structural integrity, it is essential that fracture mechanics analyses considering the behavior of defects are conducted to assess the safety margins over the service life spans of these components. Conventional fracture mechanics are based on the assumption that a single parameter (e.g. J, K or CTOD) uniquely characterizes the crack tip stress and strain fields. However, it is now well understood that a single parameter generally cannot completely characterize the crack tip stress strain fields. This gives rise to the so-called constraint effect. Significant research progress has been made over the past 18 years in characterization of constraint effects. Methods of quantifying the in-plane constraint effects using an additional fracture parameter have been well-established.

核压力容器、天然气管道、海洋工程、航空航天等高性能工程结构的安全运行具有现实意义。 为了确保结构完整性，必须进行考虑缺陷行为的断裂力学分析，以评估这些部件在使用寿命内的安全裕度。 传统断裂力学基于这样的假设：单个参数（例如 J、K 或 CTOD）唯一地表征裂纹尖端应力和应变场。 然而，现在众所周知，单个参数通常不能完全表征裂纹尖端应力应变场。 这就产生了所谓的约束效应。 过去 18 年在约束效应表征方面取得了重大研究进展。 使用附加断裂参数来量化面内约束效应的方法已经很成熟。