| The requirement for reducing noise and vibration has grown rapidly with the development of the urban rail transit (URT), at the same time various modern railway tracks have been widely used in URT. As one of the most effective railway track types for reducing noise and vibration, the floating slab track system (FST) have more and more examples in engineering applications.The aging characteristic of the rubber bearings which were widely used underneath the floating slab was investigated in this paper. The relationship between the equivalent stiffness coefficient, loss factorand and the equivalent damping coefficient of the rubber bearings and the experiment hours was derived from the accelerated aging experiment under fatigue loads. Program based on the FORTRAN language was developed to deal with the vehicle-structures coupling problem, further research was conducted to obtain the relationship between the vehicle-structures dynamics characteristic and the experiment hours. Energy transmission characteristics of the FST was studied based on the power flow method and further research was conducted to obtain the relationship between the energy transmission characteristics and the experiment hours. At the last of this paper a comparative analysis between the power flow method and the transfer function method was conducted to investigate transmission characteristics of the FST and a similar conclusion has been obtained.Following questions were investigated in this paper:(1) Different factors and typical strategies which were related to the aging characteristic of rubber bearings were analyzed generally, and then the fatigue loads were determined as the main factor influencing the aging characteristic of rubber bearings.(2) The relationship between the equivalent stiffness and damping ratio of the rubber bearings and the experiment hours was derived from the accelerated aging experiment under fatigue loads. The most important and difficult point in the accelerated fatigue experiment was how to obtain the accelerated fatigue loads spectrum. Usually the following steps were included in the whole process: data acquisition, rain-flow counting, zero-mean conversion, probability distribution checking, invalid range value filter and so on. Finally an eight-level load spectrum for the fatigue experiment was derived. (3) How the dynamic characteristic of whole part of vehicle-structures coupling system changed with the service life of rubber bearings which was usually in years? This question was answered by the vehicle-structure coupling dynamics program based on the aging characteristic of rubber bearings.(4) The power flow method which was based on the accelerated aging experiment results of rubber bearings was introduced to investigate the transmission characteristics of floating slab track from the standpoint of energy transmission. How the power flow transmission characteristic of FST was influenced by the aging characteristic of rubber bearings was also researched in this paper.(5) A comparative analysis between the power flow method and the transfer function method was conducted to investigate the transmission characteristics of the FST and a similar conclusion has been obtained.Based on the fatigue experiment results, theoretical analysis and numerical computation, the aging characteristic of FST rubber bearings was investigated in this paper, the dynamic characteristic of whole part of vehicle-structures coupling system and the transmission characteristics of the FST changed with the service life of rubber bearings was studied as a further research which should be useful of reference to engineering practice.
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