基于临界面理论的焊接结构多轴疲劳寿命评估方法

摘要

It is hard to use the current mutiaxial fatigue theory for real welded structures in engineering. An approach for multiaxial fatigue life assessment of complex welded structures is proposed, by combining the equivalent hot spot stress method and the bi-parametrical critical plane theory. The damage parameters and controls equations of the critical plane theory and the definition of the equivalent hot spot stress method are described, respectively. A procedure of the multiaxial fatigue life assessment for welded structures is pre-sented, and the feasibility of the proposed approach is verified by the use of finite element analysis.%　　目前多轴疲劳理论难以用于实际工程中焊接结构的疲劳寿命评估。文章将等效热点应力法与双参数临界面理论相结合，提出了一种能够应用于复杂焊接结构的多轴疲劳寿命评估方法。分别阐述了双参数临界面法的损伤参数、控制方程以及等效热点应力的定义，给出了焊接结构多轴疲劳寿命的评估过程，并应用有限元数值模拟验证了该方法的可行性。