Resumen:
Stochastic fatigue damage of a metro switch blade is studied with a combination of explicit finite element model (FEM), multiaxial fatigue criterion, and statistical analysis. The explicit FEM is used to reproduce dynamic procedure and to provide detailed stress/strain state variation. A multiaxial fatigue criterion proposed recently is extended to 3D conditions for fatigue prediction. The influence of stochastic impact position is considered by statistical analysis. After analysis, the formation of the serious unstable crack (continuous bites) on the switch blade can be revealed. From the perspective of service life, increasing traction coefficient and decreasing friction coefficient between wheel flange and switch blade gauge surface are beneficial but not significant. However, a speed increase from 36 to 54 km/h can lead to 40% reduction in service life. This work enhances the cognition of damage mechanism on switch blade and provides theoretical foundation for service life design and maintenance operation.
