Abstract The existing stress field evaluation formulas for V-shaped and U-shaped notches are complicated and limited to certain specific opening angles. Based on linear elastic fracture mechanics and singular strength theory, the traditional calculation formula of notch stress distribution is simplified by introducing singular intensity factors, and the notch stress formula suitable for different opening angles is further summarized and fitted by comparing the stress distribution laws from 102° to 150° opening angles. After verification, the relative error of stress between the simple formula and finite element results is about 5%. On this basis, the formula of notch stress intensity factor (N-SIF) under different opening angles is further derived. Finally, the notch stress and N-SIF of cruciform welded specimens under different welding angles are separately calculated for fatigue strength evaluation. The evaluation process shows that the simplified formula can be used to quickly and accurately evaluate the notch stress field and fatigue strength of welded structures.

中文翻译：

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不同张角V形和U形槽口奇异应力场评估的简化方法

摘要 现有的V形和U形缺口应力场评价公式较为复杂，且仅限于特定的开度角。基于线弹性断裂力学和奇异强度理论，引入奇异强度因子，简化了传统的缺口应力分布计算公式，并通过比较102的应力分布规律，进一步总结拟合出适合不同开度角的缺口应力公式。 ° 到 150° 的开口角度。经验证，简单公式与有限元计算结果的应力相对误差约为5%。在此基础上，进一步推导出不同张角下的缺口应力强度因子（N-SIF）公式。最后，分别计算十字形焊接试样在不同焊接角度下的缺口应力和N-SIF进行疲劳强度评价。评估过程表明，该简化公式可用于快速、准确地评估焊接结构的缺口应力场和疲劳强度。