DERAILMENT RISK ANALYSIS OF A TILTING RAILWAY VEHICLE MOVING OVER IRREGULAR TRACKS UNDER WIND LOADS

Based on the nonlinear creep model and Kalker's linear theory, this paper studies the governing di r erential equations of motion for a tilting railway vehicle moving over irregular curved tracks under wind loads. The tilting vehicle is modeled by a 24-degree-of-freedom (24-DOF) car system, considering the lateral, roll and yaw motions of each wheelset, the lateral, vertical, roll and yaw motions of each bogie frame and the car body. The derailment quotients of the tilting railway vehicle with the wheelsets moving over irregular rails in the lateral direction and the car body acted upon by the wind loads are investigated for various tilting angles. The analysis results show that in general, the derailment quotient of the wheelset increases as the tilting angle of the railway vehicle increases. When the railway vehicle moves at low speeds, the derailment quotient calculated for the case with rail irregularities is greater than that for the case with no rail irregularities. Moreover, the derailment quotient of a wheelset moving over curved tracks of various radii is presented. Finally, the derailment quotient computed for the case under wind loads is greater than that free of wind loads. As a result, the in uence of rail irregularities and wind loads on the derailment risk of a tilting vehicle cannot be ignored.