Mesh-size Effect Study of Extremely Low Cycle Fatigue Life Prediction for Steel Bridge Piers by Using Different Models

Prediction models based on the Manson-Coffin relation that capture interactions of plastic strain and damage index provide accurate criteria to predict ductile fracture in finite element simulations of structural steel materials and components. Three such models – Tateishi method, Xue method and Ge method – take the effect of extremely low cycle fatigue into account in different ways. Finite element simulations with three different mesh sizes for nine steel bridge piers demonstrate the application of different prediction models to evaluate the ductile crack initiation under cyclic loading in steel structures. While the refined mesh size is 1~2mm, Ge model’s results are in good agreement with experimental results. If the refined mesh size is 0.5mm, Tateishi and Xue models may be suitable. This suggests that using appropriate scale finite element model based on different prediction methods is necessary.