Study on Wheel/rail Noise for Elevated Block-Supported Track of the Urban Mass Transit

On the basis of wheel/rail noise prediction model called STTIN,characteristics of wheel/rail noise when a train running on an urban elevated block supported track,and wheel/rail noise of the block supported track is compared with that of the ballasted track.It makes clear that domain frequency of wheel/rail noise is in a range of 500～(2 000) Hz,and that the rail radiates chiefly middle and high frequency noise,and that the wheel radiates chiefly high frequency noise,and that the supporting block radiates noise in a range of middle and low frequency when the train run with a speed of 70 km/h.It is also known that the rail plays a far more important role than the wheel and the supporting block,and that wheel/rail noise is increased with the raise of running speed of the train,and that the influence of the speed on the noise radiated by the rail is more remarkable than that on the wheel and the supporting block.The wheel/rail noise of the block supported track is about 2.8～4.5 dB(A) higher than that of the ballasted track for the receiver nearby the rail.Measures should be taken to reduce the noise level of block-supported track down to the level of ballasted track or even lower.