Research on the Simulation of Wheelset Response Characteristic Identification of Railway Fastener Loosening

Abstract

Rail fastener is a crucial component equipment to ensure the safe operation of the train, and it is very paramount to detect the loose state of the fastener. In this paper, the vertical vibration acceleration signal of wheelset is taken as the research object, and the loose state of fastener is identified by separating and calculating the key IMF energy entropy. Firstly, based on the finite element theory and the principle of multibody dynamics, the rigid-flexible coupling simulation model of vehicle track is established. Then, the vertical vibration acceleration signals of the wheelset under the speed of 200 km/h are obtained by setting the different loosening degrees of the fastener. Finally, we use optimized HHT to process signals, and the orthogonal empirical mode decomposition method (OEMD) is proposed to optimize the orthogonality of the intrinsic mode function, to eliminate the IMF component having poor correlation with the original signal; the Hilbert time spectrum and information entropy theory are combined to calculate the energy entropy of the key IMF, and the HHT energy entropy evaluation algorithm of the vertical acceleration response signal of the train wheelset is proposed. The simulation results show that the HHT energy entropy of 100% fastener looseness is less than 25%, 50%, and 75%, decreasing trend. The algorithm can recognize the looseness of track fastener through the experiment under different working conditions.

Feature recognition of state signal of electromechanical integration railway turnout over health parameters using CMOS area array technology

“…Positioning and inversion action current curve, power curve, DC voltage, AC voltage, DC and AC current are analog quantities, and the analog acquisition method is adopted. On the other hand, DBJ, FBJ, 1DQJ, and 2QJ states are collected by switching value collection method [23].…”

Evaluating the Effect of Rail Fastener Failure on Dynamic Responses of Train-Ballasted Track-Subgrade Coupling System for Smart Track Condition Assessment

“…With reference to three particular defect sites on a ballasted railway track in the U.K., Thompson et al [ 22 ] proposed maintenance and repair strategies at such locations, e.g., the deflections measured during the train passages were used to determine the thickness of shims placed between the rail pad and the sleeper. Zhang et al [ 23 ] analyzed the effects of fastener looseness and failure from energy perspective, calculated acceleration responses by setting different levels of fastener looseness, and then proposed the algorithm for identifying rail fastener looseness from Hilbert-Huang Transform (HHT) energy entropy. Note that they analyzed only the vertical acceleration, while the analyses of longitudinal and transverse acceleration responses still remain unexplored.…”

“…From the above-mentioned survey of existing literature on rail fastener failure, it can be seen that the inherent mechanical mechanism of rail fastener failure was previously studied from FEM simulations [ 21 , 23 ], mainly because it is very challenging to study it from laboratory or field tests. Further, such previous numerical simulations focused on the vertical train-track coupling only with the longitudinal motion of wheel-sets rarely considered, and few longitudinal vibration analyses of the train-ballasted track coupling system existed in the literature.…”