中文摘要：

针对承受拉弯载荷作用焊趾处含有表面裂纹的 T 型焊接接头，提出了一种根据裂纹最大张口位移量确定裂纹最大深度处应力强度因子的新方法。基于有限元数值计算，考虑了模型尺寸效应、焊接尺寸、裂纹深度比、裂纹形状比等因素对应力强度因子的影响，建立了拉伸、弯曲载荷对应的修正系数表达式，提出了基于裂纹表面最大张口位移确定 T 型焊接接头裂纹深度方向的应力强度因子的简便方法。以十字形板板焊接接头为例，显示该方法适用于任意形式的板板焊接接头。

英文摘要：

A new method was proposed to calculate stress intensity factor （SIF） at the position with maximum crack depth based on maximum crack opening displacement （MCOD） for surface cracked weld toe in T-welded components subjected to tension and bending loads. Finite element method was adopted to consider the influences of the factors, such as model size, weld size, crack depth ratio, and crack shape ratio, on the stress intensity factor. The expressions of modified coefficient of SIF were established under tension loads and bending loads respectively. The crisscross plate joints are taken into account to verify the applicability of this method to any forms of welded components made from plates.