Investigation on the motion conditions and dynamic interaction of vehicle and turnout due to differential wheelset misalignment

Assembly deviations of wheelsets cause differential wheelset misalignments and change the wheel-rail contact relationship in railway turnouts. In this paper, the motion conditions of wheelsets under the same bogie are analysed with differential wheelset misalignment based on the mechanical equilibrium condition. A rigid-flexible coupling model of vehicle-turnout dynamic interaction that fully considering different misalignment conditions is established to evaluate the wheel and turnout rails dynamic interaction and vehicle dynamic characteristics. The results show that wheelset misalignment can change wheel load transition position and affect wheel-rail contact conditions, especially when the misalignment direction is toward the switch rail. The larger misalignment angle will increase flange contact range and keep the normal contact stress at a higher level. Both misalignment angle and form determine the wheel-rail vertical force. The lateral force is mainly affected by the superposition effect of the eccentric load and the lateral impact of the wheel load transition.