Crack Driving Force Calculation for a Railway Wheel Considering Thermoplastic Properties of the Wheel Material

In this paper, the driving force calculation of a cracked railway wheel is studied, and the effects of thermal loads due to braking, train speed, and elastic-plastic material model are considered. Since the wheels are subject to fatigue loading and the property of its material is elastic-plastic, the study of crack growth in them is necessary because, in the case of existing a crack in the wheel and reaching its critical lengths, the failure of the wheel will occur. This is one of the important reasons for the accidents and derailment of trains. In this paper, the investigation of crack growth in the wheel is performed by two primary methods, linear elastic fracture mechanics (LEFM) and elastic-plastic fracture mechanics (EPFM) each of them has their specific condition of use. The applicability of each method in different conditions is discussed. The results demonstrate the importance of thermal loads of braking, train speed, and cyclic hardening material behavior on the usage of different approaches to achieve the appropriate crack driving force.