دانلود رایگان مقاله اندازه گیری و مدلسازی مسیر راه آهن تعبیه شده

Abstract

A finite element (FE) model and a boundary element (BE) model have been developed to predict the decay rate, vibration and noise responses of an embedded rail track. These models are validated using measured results. The optimisation of the embedded rail track is conducted using these calculated models. The results indicate that the optimised cross-section of the gutter for the embedding rail can significantly reduce the radiated noise of the embedded rail track. The embedded rail track using the I-shaped cross-section gutter reduces the radiated noise of the track by at least by 3 dB(A). Furthermore, combining the material parameter optimisation with the gutter cross-section optimisation can further reduce the radiated noise of the embedded rail track. Increasing the Young’s modulus of the rail pad in the embedded rail track with the I-shaped cross-section gutter can result in a radiated noise reduction of 4 dB(A).

6. Conclusions

The decay rate, vibration and noise responses of an embedded rail track were measured. When a tram was running at 60 km/h, the overall sound pressure level of the wheel/rail rolling noise was 98.8 dB(A) inside the bogie, the measured noise reached its highest levels between 400 Hz and 1000 Hz, and the noise peaks in the frequency band of 400 Hz and 800 Hz were most likely caused by the radiated noise of the elastomer and the rail, respectively. The decay rate of the embedded rail was relatively lower in the frequency band of 100–1000 Hz, which most likely resulted in a longer track structure vibrating and radiating noise in this frequency range. FE and BE models have been developed to calculate the decay rate, vibration and noise responses of the embedded rail track. These models can adequately predict the vibration and noise responses of the embedded rail track and optimise the track. These models have been validated using the measured results. The overall sound pressure level of the calculated track is 97.8 dB(A), which is slightly lower than the measured one. However, it can suitably reflect the frequency characteristics of noise for the track and wheel/rail rolling.