LABORATORY EVALUATION OF PAVEMENT SURFACE TEXTURE CHARACTERISTICS IN RELATION TO SKID RESISTANCE

Four methods for measuring pavement surface texture (a Text- Ur-Meter, two Modified Sand Patch Methods, and an Outflow Meter) were utilized to determine average texture using the BPR Skid Trailer and a British Portable Tester. In a general way, both skid resistance and surface texture were found to vary with time and traffic. Plots of skid resistance speed gradient versus surface texture show a trend indicating that the greater the texture within the measured range, the less the rate of decrease in skid number with increasing speed. However, no consistent correlation was obtained between any set of texture measurements and skid resistance numbers included in this study. It is concluded that while any of the texture measurement methods used is to be preferred to qualitative word descriptions, none fo these methods is comprehensive enough to be completely satisfactory. Accordingly, there is definite need for further research to develop a standard comprehensive method that will take into consideration both microtexture and macrotexture measurement.