Abstract
In the present paper the causes of the noise radiated from the railway track under the running vehicles are discussed. The unevenness of rail surfaces was measured precisely by the roughness meter and the corrugations with the amplitude of less than 10m and the wave length of 5 through 10cm were detected. The elastic constants between the wheel and the rail were also estimated by applying the load through the wheel to the rail head which was moved by every 1cm. It was found that they are scattered in the mode of Gaussian dispersion. The standard deviation of the depression between the wheel and the rail amounts to 7.6m and this deviation is presumed also to be the cause of the vibration of the rail under the running vehicles.
