Wheel–rail stochastic dynamics and rail wear analysis of small radius curved sections of a tram line based on generalized probability density evolution

Abstract

Compared with ordinary railways, the curve radius of tram lines tends to be smaller, with minimum values of only 30 m. Therefore, wheel–rail interaction is more intense and complicated in sections of small radius tram line curves. Using a stochastic variable sample set based on a generalized probability density evolution method, the stochastic variable–spectrum representation method was used to generate a time-domain sample set of stochastic track irregularities. By inputting the stochastic set of track irregularities into a tram-track coupled dynamic system model, the stochastic dynamic response of the coupled dynamic system can be obtained. Moreover, by substituting the stochastic dynamic system response into the generalized probability density evolution formula, the process of probability density evolution of each evaluation index can be obtained by the finite difference method. Finally, the dynamic response of the tram-track coupled dynamic system can be evaluated by the probability distribution of each index. By setting a series of specific groove rail wear values, a tram-track coupled dynamic analysis was carried out, and compared with the specification requirements, vehicle safety limits under different wear values were obtained. This research has great engineering value for guiding the routine maintenance of small radius curve sections of trams.

Dynamics Response of Rail Vehicle Induced by Incorporating Electric-Dominated Transmission Component

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“…During operation [1], the electromagnetic torque outputs by traction motor would act on the pinion shaft through the elastic coupling. The big gear and the axle were in interference fit, and then could drive the wheel-set [2][3] [4]. Through the motor control unit, the smooth speed regulation of the motor could be realized, and then the speed regulation of the rail vehicle could be achieved.…”

Dynamic interactions of tram-turnout coupling system in embedded turnout area

“…The trace method [19] was employed to determine the wheel-rail geometric contact relationship between the tram and embedded turnout. The Hertz normal contact theory and creep-slip theory [20,21] were adopted to analyze the normal and tangential interactions between the wheels and rails, and to establish the wheel-rail contact models of the vehicle passing through the embedded turnout [22]. Then, using the wheel-rail normal and tangential contact models in the turnout area, the multi-rigid body dynamics model of the tram and the finite-element dynamics model of the embedded turnout were coupled into the dynamics model of tram-turnout coupling system.…”

Experimental Research on Vibration-Damping Effect of Combined Shear Hinge Prefabricated Steel Spring Floating Slab Track

“…Therefore, urban express rail transits have been rapidly developed to meet the medium- and long-distance travel requirements of urban residents [ 4 , 5 ]. However, due to the normally dense land use in urban areas, urban express rail transits often pass very close residential areas [ 6 , 7 , 8 ]. For this reason, urban express rail transit is likely to have a greater impact on the environment, particularly in terms of vibration and noise caused by train operation.…”