Study on the Effect of Ballast Stiffness on Vehicle-line Dynamic Responses in Turnout Area of Urban Rail Transit

Serious rail wear in turnout area is a general phenomenon existing in urban rail transit lines in China. The reason is that bad turnout line conditions and complex turnout structures lead to large dynamic responses between vehicle and turnout, and large dynamic responses effect vehicle safety and comfort as well as lead to serious rail wears when the vehicle passing through the turnout. So how to improve vehicle comfort and control rail wears is an important research in turnout area design. Among factors effect vehicle-turnout dynamic responses, ballast stiffness is an important one. So based on analyzing the structure character of urban rail turnout, a vehicle-turnout dynamic model simulating train passing through 9-sized turnout is established. By this model, dynamic responses between vehicle and turnout in different ballast stiffness conditions are calculated and analyzed. Finally, improving advices are proposed to ballast stiffness of turnout area and references are brought to turnout design in urban rail transit.