Virtual Experiments to Predict Bolster Fatigue Lifetime Based on FEM Model Validated by Static Tests

To study the service safety of a metro train bolster, a virtual experiment method was used to evaluate fatigue lifetime, avoiding time-consuming and expensive fatigue tests. A static test of the bolster was designed based on the EN12663-1 standard, and the stresses and displacements on its surface were measured. An FEM model of the bolster was then established and analysed for comparison with the static test results; an FEM model that is consistent with the actual structure was thus determined. Finally, virtual experiments of the bolster under constant amplitude loads and variable amplitude loads were conducted using a Monte Carlo method. It is concluded that the fatigue reliability of this bolster with 10⁷ loads cycles is 0.73 under constant amplitude loads and 0.81 under variable amplitude loads. This metro train bolster therefore meets the design and service requirements.