Study On The Dynamic Performance And Influence Of Wheel/Rail Interaction For The Heavy Haul Wagon Passing The Turnout

Heavy haul freight is the development direction of China’s railway transportation. With the improvement of traffic volume, the wheel-rail force between the train and track increases significantly, especially in the turnout zone. Turnout plays an important part in connecting different railway track. Excessive wheel-rail force will cause damage to the accessory components of turnout, reduce the service life of turnout and increase the maintenance work and maintenance costs, thus increasing the operating costs. Besides, due to the variation of switch’s cross-section, the wheel-rail contact geometry condition is very complicated. The variation of wheel-rail contact geometry condition has great influence on the dynamic performance of railway vehicle. Therefore it is necessary to conduct research on the coupled vibration between vehicle and track when heavy haul freight passes the switch.This paper begins with a brief overview of the research status of vehicle-track coupling dynamics. Based on this, a vehicle-track coupling dynamic model is built. Firstly, a dynamic simulation model of NO.12 simple turnout and a dynamic model of heavy haul wagon assembled with heavy haul bogies are established with the use of multi-body software SIMPACK. Besides the characteristic of variation of switch’s cross-section, the elastic contact between wheel and rails in turnout and the multi-point contact are also considered during the establishment of simple turnout. The contact between guard rail and wheel back is also taken into consideration. Nonlinearities such as the wheel/rail interaction force, the wheel/rail contact geometry and the suspension characteristic in the model of vehicle are considered. In order to simulate the influence of wheel-rail force on the structure under the track, force elements to simulate fastener, cushion rubber, sleeper and blast are also built.The dynamic performance of vehicle-track coupling model is calculated and analyzed. To ensure that the coupling model can reflect the general vibration regularity of the system, the simulation result is compared with those in documentations. Based on this, the influence of parameters of track structure such as the stiffness of crush rubber under the track, the vertical stiffness of blast, the lateral stiffness of fastener and the key parameters of vehicle such as the lateral stiffness, the vertical stiffness, the vertical damping of primary suspension and the unsprung weight on the wheel-rail force, the safety index, the vibration of structure under track and carbody.The simulation result indicates that parameters mentioned above have great effects on the wheel/rail interaction force. By setting these parameters properly, under the premise of guaranteeing the safety of vehicle’s operation, the dynamic wheel/rail interaction and vibratory response of system can be reduced effectively.