Abstract In order to simplify the assessment method of notch stress and fatigue strength for cruciform welded structures in ocean engineering, a simple stress assessment formula based on singular strength values a s i and b s i was presented according to linear elastic fracture mechanics and notch stress strength theory. In view of the stress singularity caused by the V-notch, the stress of the corresponding U-notch was recommended and used for fatigue evaluation. Therefore, on the basis of V-notch stress formula, a simplified U-notch stress field evaluation formula was obtained by theoretical analysis and numerical calculation. After a series of verification, it is found that the stress distribution and fatigue strength evaluation formula for cruciform welded joints based on singular strength values proposed in this paper can simply and accurately predict the notch stress at welded joints. The result of fatigue strength evaluated by the simplified formula has a smaller scatter band.

中文翻译：

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U形缺口奇异应力场和疲劳强度的简化评估方法

摘要 为了简化海洋工程十字焊接结构缺口应力和疲劳强度的评估方法，根据线弹性断裂力学和缺口应力强度理论，提出了一种基于奇异强度值asi和bsi的简单应力评估公式。针对V型缺口引起的应力奇异性，推荐使用对应U型缺口的应力进行疲劳评价。因此，在V型缺口应力公式的基础上，通过理论分析和数值计算得到了简化的U型缺口应力场评价公式。经过一系列的验证，发现本文提出的基于奇异强度值的十字形焊接接头应力分布和疲劳强度评价公式可以简单准确地预测焊接接头处的缺口应力。用简化公式计算的疲劳强度结果具有较小的散射带。