Wang Yixun, Luo Yuxiao, Kotani Yuki, Tsutsumi Seiichiro
Joining and Welding Research Institute, Osaka University, Osaka 567-0047, Japan.
Department of Structural Engineering, Tongji University, Shanghai 200092, China.
Materials (Basel). 2021 Mar 6;14(5):1249. doi: 10.3390/ma14051249.
The existing curves by effective notch stress to assess the fatigue life of gusset welded joints can result in reduced accuracy due to the oversimplification of bead geometries. The present work proposes the parametric formulae of stress concentration factor (SCF) for as-welded gusset joints based on the spline model, by which the effective notch stress can be accurately calculated for fatigue resistance assessment. The spline model is also modified to make it applicable to the additional weld. The fatigue resistance of as-welded and additional-welded specimens is assessed considering the geometric effects and weld profiles. The results show that the error of SCFs by the proposed formulae is proven to be smaller than 5%. The additional weld can increase the fatigue life by as great as 9.4 times, mainly because the increasing weld toe radius and weld leg length lead to the smaller SCF. The proposed series of curves, considering different SCFs, can be used to assess the welded joints with various geometric parameters and weld profiles.
现有的通过有效缺口应力来评估节点焊接接头疲劳寿命的曲线，由于焊缝几何形状过度简化，可能导致精度降低。本文基于样条模型提出了角接焊接接头焊态下应力集中系数（SCF）的参数公式，利用该公式可精确计算有效缺口应力以进行疲劳抗力评估。样条模型也进行了修正，使其适用于附加焊缝。考虑几何效应和焊缝轮廓，对焊态和附加焊接试件的疲劳抗力进行了评估。结果表明，所提公式计算的应力集中系数误差被证明小于5%。附加焊缝可使疲劳寿命提高多达9.4倍，主要是因为焊趾半径和焊脚长度的增加导致应力集中系数减小。所提出的考虑不同应力集中系数的系列曲线，可用于评估具有各种几何参数和焊缝轮廓的焊接接头。
