Abstract In order to evaluate notch effects and size effects on fatigue performances, smooth specimens without stress gradient and a group of notched specimens particularly designed are investigated in this paper. From the perspective of probability, the statistical size effect of the latter is worth studying for bodies weakened by notches. A unified model of combination of the improved theory of critical distance (TCD), along with the concept of highly-stressed-volume (CHSV) is established to identify the initiation crack size, evaluate the fatigue strength, and determine the fatigue lifetime of notched members, and even similar large-scale components in high cycle fatigue regime. The predicted results are compared with the experimental data sets taken from literatures. Fortunately, we find that, the novel model not only inherits the generality of existing methods, such as TCD, but also provides necessary support for predictions of characteristic length and fatigue lifetime of components containing any blunt-notch geometries.

中文翻译：

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钝缺口结构构件特征尺寸及疲劳寿命计算

摘要 为了评估缺口效应和尺寸效应对疲劳性能的影响，本文研究了无应力梯度的光滑试样和一组专门设计的缺口试样。从概率的角度来看，后者的统计尺寸效应对于被缺口削弱的物体是值得研究的。建立了改进临界距离理论（TCD）与高应力体积（CHSV）概念相结合的统一模型，以识别起始裂纹尺寸，评估疲劳强度，确定缺口疲劳寿命。构件，甚至是高周疲劳状态下类似的大型部件。将预测结果与文献中的实验数据集进行比较。幸运的是，我们发现，