Conference_programme: 16: Railway noise
Lecture: Influence of Sleeper Type on Train Emission
Author(s): Weiss Bernhard, Tietze Thomas, Schmid Roman, Mach Michael, Achs Guenther
Summary:
The sound radiation of railway vehicles is based on complex interrelations between track superstructure and vehicle. In the low train speed range the wheel-rail contact is the primary source of sound and vibration. Therein, primary and secondary airborne noise is generated by rail, superstructure and boogie. In the framework of airborne sound propagation on ballasted tracks the sleeper type seems to be of great importance on the subjective perception of the vehicle emission. In this report, In this report, the difference between wooden sleepers and concrete sleepers is tested based on in situ measurements.\nWithin an extensive project, where the radiated sound power spectra of urban railway vehicles in Vienna were evaluated, the emissions on wooden and on concrete sleepers in a ballasted track bed were measured and compared. Therefore, the sound power spectra and the psychoacoustic parameter of sharpness were estimated and compared. The measurements were carried out on a straight track were the sleeper type changed from wooden to concrete, featuring one cross section for each sleeper type, respectively. The distance between the two cross sections was approximately 200 meters, enabling the measurement of trains passing the two cross-sections at constant velocity with comparable acoustic environment.\nThe comparison of the A-weighted sound power showed that the train emission on wooden sleepers is between 0.6 and 2.1 dB(A) higher than on concrete sleepers, depending on vehicle type and train speed. The difference spectra therein indicated two dominant areas that shall be explained. The different acoustic and mechanic properties of the two sleeper types and the ballast-structure are analyzed and correlated with the spectral differences and the acoustic sharpness is evaluated showing slightly higher values for the emissions on concrete sleepers.\n
Corresponding author
Name: Dr Bernhard Weiss
e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
Country: Austria
