基于J～Q双参数准则的含缺陷焊接接头失效评定曲线(Ⅰ)

Failure assessment curve of double-parameter J-Q criterion of welded joints containing defects ( I )

针对应力三轴性对裂纹尖端应力应变场的影响 ,结合均匀材料裂纹结构应力应变场的研究成果 ,提出了能反映焊接接头裂端实际应力应变场的J～Q双参数准则 ,并在此基础上得到了含缺陷焊接接头失效评定曲线的建立方法。通过有限元计算 ,分析了材料组配以及裂纹几何对文中所建立的焊接接头失效评定曲线的影响。基于工程实际 。

In terms of the influence of stress-triaxiality on stressstrain field near crack tip and the characteristics of stress-strain field of homogenous materials containing defect, the double-parameter J - Q criterion (J:J-integratian, Q:stress trixial factor), which shows the nature of stress-strain field of welded joint, is put forward. Based on the doubleparameter J-Q criterion, the failure assessment curve of welded joints containing defect is achieved. The effects of different geometrical dimensions and mis-matehed materials on the founded failure assessment curves of welded joints are analyzed by finite element method. The application of the failure assessment curve of welded joints containing defects based on engineering practices is also discussed.