Propagation of a Fatigue Crack on the Surface of Side Frame of a Freight Bogie under Irregular Operating Loads

摘要

We study the kinetics of propagation of fatigue cracks on the surface of side frame of a rail car with regard for the stochastic nature of the operating load. Its dependence on the initial geometry of the crack is established. Moreover, under given loading conditions, we determine the shape of semielliptic contour of the fatigue crack characterized by the highest growth rate into the depth of the frame wall. We also formulate a mathematical model suitable for the evaluation of the residual service life of the side frame containing a surface cracklike defect with given initial area.