Research On The Continuously Testing Method And Device Of Wheel-rail Force On The Ground

The dynamic indexes related to traffic safety,such as derailment coefficient and rate of wheel load reduction,are closely related to wheel-rail force.Therefore,the accurate measurement of wheel-rail force is of great significance in theoretical research and engineering practice.The wheel-rail force data collected by ground devices can provide a basis for real-time monitoring of vehicle status and dynamic performance evaluation.Through the real-time measurement and data acquisition of the wheel-rail force,the dynamic performance and state of the vehicle system are judged accordingly,which is one of the important means and ways to smoothly implement the state repair of the wagon.In this paper,the following aspects are studied for the method and device for measurement of wheel-rail force on ground:(1)By establishing the finite element model of the rail,the dynamic response of the rail under the vertical moving load is analyzed.The response of the reaction force of each sleeper and the output curve of the vertical force bridge are studied,and the vertical inversion method of the vertical force using the rail as the load sensor is determined.The method of counter-force and shear compensation can accurately invert the vertical force signal with high precision.And through the comparative analysis with the continuous measurement based on shear force method,the application range of the two inversion methods is pointed out.(2)The strain field distribution of the rail under the lateral moving load is analyzed.The arrangement method of the variable piece and the output curve of the bridge are studied,and the test layout sites with high linearity and good sensitivity are found,which certain accuracy is guaranteed.The error of the measurement method is analyzed through the simulation calculation.The research shows that when the value difference of a pair of lateral moving loads is large,the small value of the lateral force has a large inversion error.(3)The strain response of the rail under the coupling of vertical force and lateral force is studied.It is determined that the main source of crosstalk is the effect of vertical moving load on the lateral force bridge.An inversion step to eliminate vertical crosstalk is proposed by calibrating the transverse force bridge under vertical force.The simulation results of the bridge output are compared with the laboratory test results.The results show that the simulation is in good agreement with the test results.Finally,the test equipment was introduced.