Comparative Analysis On Test Theory Of Rail Temperature Force In Continuous Welded Rail

With the development of high speed and high-haul railway lines, the continuous welded rail(CWR) has been used around the world. When the temperature changes, it would produce a high longitudinal force which could lead to railway structure’s bucking and do harm to the safety operation. Therefore, we need to grasp the change of temperature force accurately, it is important to study the testing method of temperature force in the CWR that can measure the temperature force accurately so as to ensure the safety and stability of driving.Based on the lateral displacement method and the rail lifting method as the research object, contrastive analysis the influence of temperature force value with the load deviation, fastener rigidity, rail wearing and calibration length factors. First this paper introduces the testing principle of the two test methods, using the mechanics model of CWR to infer the formula of the temperature force, theoretical analysis the influence of temperature force value with the external load deviation factors; Then using ANSYS to establish the finite element model of CWR, the theoretical results of the mechanical model and the simulation results of the finite element model are compared to verify the validity of the simulation model; Finally based on the simulation model to analysis various working conditions, by changing the external load deviation angle, fastener rigidity, rail wear volume size, calibration length of the lateral displacement method and the rail lifting method to analysis the influence of the temperature force value on the straight line and curve track.Results show that the external load deviation and calibration length have a great effect on the lateral displacement method and the rail lifting method of temperature force value results, after comparative analysis of the two methods can show that the influence of the temperature force value results of the rail lifting method affected by external load deviation and calibration length is more larger; fastener rigidity, rail wearing have little influence on the temperature force value results of the lateral displacement method, the factors have big influence on the temperature force value results of the rail lifting method; with the increase of curve radius, the load deviation, fastener rigidity, rail wearing and calibration length factors on the value results of rail temperature force increasing, the influence of the straight line track is largest.Compared with the straight line track, curve track of the value of temperature force with external loads factors have higher accuracy; comparative analysis based on lateral displacement method and rail lifting method, lateral displacement method can achieve more precision with measurement of rail temperature force in the CWR.