The author examines the use of various systems of road edge marking to provide and auditory signal to warn drivers of overrunning. An earlier French trial is outlined and the method used in this investigation described. Tests were carried out on a stretch of the South Gippsland Highway in Australia using a Toyota sedan, a 4-wheel drive Nissan vehicle and a 6-axle articulated vehicle. Three different heights of marking, 4mm, 6mm and 8mm were tested in combination with 3 different spacings, 50mm, 250mm and 450mm. The frequency characteristics of the noise are discussed. The 6 and 8mm material at 50 or 250mm gave adequate signals for both cars but little change in noise was obtainable with the truck. For the covering abstract see C 45915 (IRRD 876074).
Abstract