Dynamic Response of the Track Irregularity State in a Subway Turnout Zone

Aiming at the environmental vibration problems of turnout zone, the vibration equations for vehicle and turnout system are developed respectively by means of finite element method and Lagrange equation. According to irregularities characteristics of turnout structure, the wheel/rail contact geometry is introduced to the vehicle-turnout coupling system. Then the computational software is coded with Matlab. Dynamic responses of the irregularities state are analyzed. The calculation results show that large impact of vehicle-turnout system is produced when vehicle passing through the switch area and frog area. The vertical geometric irregularity of turnout has significant influence on wheel/rail interaction force, where turnout wear aggravates this dynamic action. To improve the turnout working state and reduce the maintenance cost, the occurrence and development of wear in frog area should be controlled strictly.