Model-supported analysis of comparative rolling noise measurements on two types of railway tracks

Paper i proceeding, 2024

Rolling noise measurements of in-service trains have been carried out at the demonstrator of a new type of slab track (the “3MB” originally devised in the FP7 Capacity4Rail project) and an adjacent ballasted track section on the iron ore line in Northern Sweden in May 2023. The analyses of the measurement data showed an increase in equivalent pass-by sound pressure levels (SPLs) at the slab track compared to the ballasted track, with, on average, about 2 dB observed at 7.5 m from the track. There was, however, a large spread in the results dependent on overall SPL, train speed, train type, and train individual. In addition to the pass-by measurements, a detailed characterization of track dynamics and rail roughness has been carried out. These latter measurements partially explain the observed differences in SPL, but more insight can be gained with a comprehensive model for rolling noise adapted to the conditions at the measurement site. In particular, the role of the rail roughness is investigated by simulations.