The purpose of this paper is to present the extension of a previously developed strain-based fracture mechanics (SBFM) model from one to two dimensions for simulating fatigue crack growth in steel arc welds. The one-dimensional (1D) SBFM model is first briefly reviewed. Steps for extending it to simulate 2D growth of a semi-elliptical surface crack in a weld are then described. An application of the new model is lastly presented, which consists of analysing the behaviour of structural steel weld specimens from a previously published fatigue test program, in which the fatigue performance of weld specimens was enhanced by high frequency mechanical impact (HFMI) treatment. In this application, the effect of the treatment-induced compressive residual stress on the crack shape is simulated, and it is shown how the extended 2D SBFM model can be used to establish probabilistic design stress-life (S-N) curves for various loading conditions.

本文的目的是提出一种先前开发的基于应变的断裂力学（SBFM）模型从一维到二维的扩展，以模拟电弧焊中的疲劳裂纹扩展。首先简要回顾一维（1D）SBFM模型。然后描述了将其扩展以模拟焊缝中半椭圆形表面裂纹的2D增长的步骤。最后介绍了新模型的应用，该模型包括根据先前发布的疲劳测试程序分析结构钢焊接试样的行为，其中通过高频机械冲击（HFMI）处理来提高焊接试样的疲劳性能。在此应用中，模拟了处理引起的压缩残余应力对裂纹形状的影响，