The Noise and Vibration Response of Eight Light Vehicles on Sinusoidal and Conventional Rumble Strips

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. The measurements were performed at 97 km/h and 72 km/h. The primary purpose of the measurements was to develop a recommendation for a standard rumble strip evaluation procedure that could be implemented by transportation agencies to assure comparable results when considering rumble strip designs that produce minimal exterior noise while maintaining sufficient warning input to the vehicle operator. This research did reveal some markedly different results between the test vehicles in both interior noise and vibration as well as pass-by noise. In this paper, these results are presented, and initial draft test procedures are reviewed.