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Noise and vibration measurements were conducted on eight light vehicles ranging from small compact passenger cars to a large sport utility vehicle on and off shoulder rumble strips of two different designs to assess the input to a vehicle operator when the vehicle departed from the travel lane. The first design was a more conventional design, consisting of cylindrical indentions ground into the pavement at regular 30 cm intervals, and a continuous sinusoidal profile with a peak-to-peak length of 36 cm. Triaxial vibration measurements were made at six locations, including the steering wheel and column, the seat cushion and track, and the front and rear spindles. Interior noise was measured at six locations, one at the operator’s outward ear and five at the front seat passenger (three in the fore/aft locations of the seat and at outboard and inboard ear locations). In addition to the in/on vehicle measurements, pass-by noise levels were made.

Typically, the noise emission from trucks under highway cruise conditions is not reduced as much as it is for light vehicles when quieter pavements are used. Potential reasons for this are that other noise sources beside tire/pavement noise are more significant for trucks than light vehicles and/or the effect of pavement on truck tire noise generation is different than it is for light vehicle. As the cruising passby noise levels of trucks are about 10 dB greater than for light vehicles, this becomes an important issue for highway noise abatement when trucks make up even a relatively small percentage of the traffic flow. To investigate this issue, beam forming and conventional passby testing methods were used to investigate the contribution of both tire/pavement noise and the other noise sources for common types of heavy trucks.

At speeds of 50 km/h or greater, the exterior noise emission of light vehicles is typically dominated by tire/pavement noise for operating conditions of cruise and moderate acceleration. At a test speed of 56 km/h, it has been found that pavement type can create a 10 dB or more variation in tire/pavement noise. This has significant implications for both community noise and vehicle noise emission testing. In this paper, the results of tire/pavement noise measurements for over 80 different pavements in Europe and the United States are reported. These pavements include research surfaces, existing roadways, and ISO 10844 passby test surfaces. Measurements were conducted using an on-board sound intensity methodology that has been correlated to cruise-by noise levels. These results are discussed in terms of the revisions being considered for the ISO 362 passby test procedure and the ISO 10844 test surface specification.