The rolling noise is studied of 8 sets of truck tyres, consisting of four sets of originals tyres and four sets of their nearly identical retreaded versions. Tests are performed according to the R117 (1) procedure on regulated ISO 10844 surface and on three additional surfaces. Tests consisted of coast-by conditions at speeds between 40 and 80 km/h. Both SEL and LAmax values in one-third-octave bands are recorded at the standard positions on 7,5 m distance and 1,2 m height. A height of 3,0 m was added. Overall A-weighted levels and 1/3rd octave spectra are recorded. The tyre sets in this study comprised of two trailer types and two traction types. In order to identify the shifts in acoustic relevant tyre properties caused by retreading, also the tread profile geometry, the tread rubber hardness and the tread mobility is recorded of the tyres under test. We observed an increase in noise level from the retreaded version compared to the original one. This increase manifests itself in different spectral areas. The tread rubber hardness and the tread band mobility did show shifts after retreading but these shifts could not be related to the shift in rolling noise levels. Also no effect of the tread geometry could be observed.
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