VIBROACOUSTIC DYNAMICS SIMULATION OF RAIL ON SLEEPERS

Abstract

The theoretical investigation of the noise and vibration of the rail as a line limited distance elastically mounted source is resulted. When installing the rail on sleepers, it is presented as a system of two-point sources simultaneously radiating the sound energy, and every section of the rail between the sleepers – as a line limited distance source. The dependences of the sound pressure produced by the rails are obtained for such a source. It permits to specify the noise emission pattern in low and high frequencies of the rated audio band. Two options for installing the rail on wooden and concrete sleepers are considered. In the first case, the differential equation is solved for the rail vibration pinning conditions, in the second – for the rigid fixing conditions. On the basis of the theoretically calculated vibration velocities at natural frequencies, the acoustical radiation spectra are defined. The obtained dependences consider both engineering data and stress-strain properties of the noise source, and the effective loss index of the vibration energy which allows choose theoretically the option of reducing the rail sound emission intensity.