The Master S-N curve method enables the use of computationally efficient coarse FE models without overlooking accuracy in fatigue life estimates of welded structures. However, the use of the method in daily design practice of engineering offices faces the barrier of a largely available finite element post-processor. This paper intends to fill the gap on how to implement a finite element structural stress post-processor for the Master S-N curve method in FEM software. Previous overlooked aspects of the Master S-N curve method in literature such as how to deal with solid and quadratic elements and how to smooth stress singularities with the Generalized virtual node method or using a rounded weld end are fully explained. Three demonstration examples of welded connections are illustrated and validated: (a) a uniaxial longitudinal welded attachment using linear/quadratic solid elements, (b) a flat plate subjected to high bending stresses and using a simplified representation of the weld end with quadratic shell elements, and (c) a welded tube subjected to multiaxial loading using shell and solid elements. The proposed algorithms show the full capabilities of the developed Structural Stress Post-processor for fatigue analysis of welded structures under constant amplitude loading and multiaxial stress states.

Master SN 曲线方法允许使用计算效率高的粗略有限元模型，而不会忽视焊接结构疲劳寿命估计的准确性。然而，在工程办公室的日常设计实践中使用该方法面临着大量可用的有限元后处理器的障碍。本文旨在填补如何在 FEM 软件中为 Master SN 曲线方法实现有限元结构应力后处理器的空白。之前在文献中被忽视的 Master SN 曲线方法的方面，例如如何处理实体和二次元素以及如何使用广义虚拟节点方法或使用圆形焊接端来平滑应力奇点。说明和验证了焊接连接的三个示范示例：(a) 使用线性/二次实体单元的单轴纵向焊接附件，(b) 承受高弯曲应力的平板，并使用二次壳单元的焊接端的简化表示，以及 (c) 承受多轴应力的焊接管使用壳单元和实体单元加载。所提出的算法显示了开发的结构应力后处理器的全部功能，用于在等幅载荷和多轴应力状态下对焊接结构进行疲劳分析。