Highly Stressed Volume Approach in Size Effect Analysis of Fatigue: State of the Art

With increasing structural size of main components and increasing demand for service safety, higher reliability index demand is imposed, promoting the development of life prediction theories considering size effect. Size effect refers to the influence of structural size on the fatigue strength. However, traditional fatigue life design theories are normally developed based on small-scale material level tests, and the size factor is then utilized for quantifying the size effect. As an effective method for size effect modelling, the highly stressed volume (HSV) approach provides accurate description and robust transfer of fatigue performance between structures with different sizes. Development history and basic analysis process of fatigue life assessment under size effect were systematically reviewed. Development status as well as the HSV-based size effect modelling framework were summarized. Predictive ability of the HSV approach was compared with the theory of critical distance and weakest link theory as well as their advantages and disadvantages. Finally, development bottleneck was summarized, and future trends were prospected.