Theoretical investigation into the formation mechanism and mitigation measures of short pitch rail corrugation in resilient tracks of metros

Abstract

Severe rail corrugation occurs at both the curved and tangent tracks of the metro in Shanghai, where resilient rail fasteners are used to reduce ground-borne vibration by isolating the transmission of track vibration to the infrastructure. The wavelength of corrugation is about 25-30 mm. It could be assumed that this short pitch rail corrugation is caused by the pinned-pinned resonance. However, rail fasteners with low stiffness were believed to be able to suppress the pinned-pinned resonance thereby resulting in corrugation. To investigate the formation mechanism of this specific rail corrugation, a multiple wheel-rail interaction model is used to calculate the wheel-rail dynamic forces caused due to the multiple wheel-rail interactions, which are considered to play a major role in the formation of corrugation. Then the influences on wear and corrugation growth are analyzed in terms of both amplitude and phase of the wheel-rail dynamic forces. By combining the properties of multiple wheel-rail interactions with their influences on wear and corrugation, the growth rates of rail corrugation at different wavelengths (frequencies) are studied to obtain the characteristic wavelength (frequency), at which the highest corrugation growth rate appears. The obtained characteristic wavelength is in good agreement with observation in the practice of Shanghai metro. It is found that the wave reflection from the wheels on the rail is responsible for the short pitch rail corrugation in the resilient tracks. Finally, tuned rail dampers are applied in the multiple wheel-rail interaction models to investigate their effects on rail corrugation growth. The simulation results show that use of tuned rail dampers is effective in suppressing the short pitch rail corrugation occurring at resilient tracks.

Theoretical investigation into the measurability of rail unevenness and corrugation using the dynamic response of axle box and bogie

“…The first four peaks are located at 160 Hz, 365 Hz, 625 Hz, and 930 Hz respectively, which are in accordance with those in the wheel–rail interaction force at wheel 1 in Fang et al. 19 and Wang and Wu. 20 These are believed to be caused by the standing wave formed between wheels, which can be proved by the rail vibration magnitude | X r ( z )| presented in Figure 5(b).…”

“…Moreover, the resonances for the displacement response of two axle boxes to unevenness for four-1/8-vehicles model are consistent with those in the liner and nonlinear wheel–rail interaction force 19,20 at wheels 1 and 2 under multiple wheel–rail interaction, respectively, so does the resonance for the single-1/8-vehicle model. It means that the vertical vehicle–track interaction model developed in Figure 1 can be used to investigate the measurability of rail unevenness and corrugation by dynamic response of axle box and bogie.…”

Rail Corrugation Characteristics of Cologne Egg Fastener Section in Small Radius Curve

“…Wen [18] Combining the vertical coupled dynamics of vehicle-rail, unsteady rolling finite element model and twodimensional rolling contact model of cater, the calculation model of corrugation of plastic flow pattern was established Wu et al [19] Fractal description of rail corrugation was established Zhang et al [20] Causes and treatments for corrugation developed on Egg fastener track Li et al [21] Using field observations, experiments and numerical study were conducted to investigate the occurrence mechanism of corrugation Cui et al [22] Corrugation was caused by friction, self-excited vibration between wheels and rails Fang et al [4] Formation mechanism and mitigation measures of short pitch corrugation 2 Shock and Vibration…”

“…Corrugation is a kind of defect on rail heads, which is characterized by periodic irregularity of rail surface, and its shape is similar to that of wave. Corrugation occurs to varying degrees in metro systems all over the world, especially in small radius curve sections [1][2][3][4]. e wavelength of corrugation is generally between 20 mm and 300 mm, and the wave depth is not more than 1 mm [5].…”

Wheel–rail dynamic interaction caused by wheel out-of-roundness and its transmission between wheelsets

“…The transmission of wheel-rail interaction between multiple wheelsets has been considered not to be neglected in the study of rail corrugation. [43][44][45][46] Igeland 43 developed a two wheels-rail interaction model to investigate the wheels-rail interaction and found that the two wheelsets of a bogie interacted and the wheelbase was an important parameter for rail corrugation growth. The effect of multiple wheelsets on the wheel-rail normal contact force was also been investigated by Wu and Thompson.…”