Multiaxial fatigue assessment of complex steel connections: A case study of a vertical-lift gussetless truss bridge
Multiaxial fatigue assessment of complex steel connections: A case study of a vertical-lift gussetless truss bridge
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DOI：
10.1016/j.engstruct.2021.111996
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发表时间：
2021-03-11
影响因子：
5.5
通讯作者：
Bell, Erin Santini
中科院分区：
文献类型：
--
作者：
Tchemodanova, Sofia Puerto;Mashayekhi, Maryam;Bell, Erin Santini
土木工程结构变得更加复杂，因为工程师推动创新边界。负载复杂性、成本、施工和维护效率等因素可能导致独特的设计，而这些设计往往被排除在当前的设计规范和评估标准之外。疲劳损伤是目前桥梁等普通和复杂土木工程结构在循环荷载作用下最常见的损伤类型之一。然而，目前的疲劳评估和设计标准对如何处理复杂的焊接连接提供了有限的指导。单轴和多轴疲劳寿命的评估方法，使用应变历史进行比较，为评估的焊接无角撑板桁架连接的纪念桥，垂直升降桥连接朴茨茅斯，NH和基特里，ME。正如预期的那样，使用这两种方法会导致足够的剩余疲劳寿命。然而，它表明，常用的单轴疲劳分析方法可能是不够的，在复杂的结构，经历变幅，多轴，和非比例加载。复杂连接所经历的多轴非比例应力会导致剩余疲劳寿命估计值降低。本文提出了利用应变时程评估复杂焊接接头疲劳寿命的评估工具和方法。
Civil engineering structures grow more complex as engineers push innovation boundaries. Load complexity, costs, construction and maintenance efficiency, among other things, can lead to unique designs that are often excluded in current design codes and evaluation standards. Fatigue-induced damage is currently one of the most common damage types experienced by ordinary and complex civil engineering structures subjected to cyclic loading such as bridges. However, current fatigue evaluation and design standards provide limited guidance on how to approach complex welded connections. Uniaxial and multiaxial methods for the evaluation of fatigue life using strains histories are compared for the assessment of a welded gussetless truss connection of the Memorial Bridge, a vertical-lift bridge connecting Portsmouth, NH and Kittery, ME. As expected, using both approaches result in sufficient remaining fatigue life. However, it is demonstrated that commonly used uniaxial fatigue analysis methods can be insufficient in complex structures that experience variable amplitude, multiaxial, and non-proportional loading. Multiaxial non-proportional stresses experienced by a complex connection can cause a decrease in remaining fatigue life estimates. This paper presents assessment tools and a method for the evalu-ation of fatigue life of complex welded connections using strain time histories.