Measurement of pavement macrotexture with circular texture meter

The results of tests conducted with the circular texture meter (CTMeter), which measures the profile of a circle approximately 800 turn in circumference, are discussed. It is shown that by analyzing the profile data obtained with the CTMeter one can obtain reliable predictions of volumetric mean texture depth (sand patch texture depth) and the outflow times of several designs of outflow meters. Data from 3 years of testing are used to evaluate the correlation of the mean profile depth obtained with the CTMeter to the volumetric mean texture depth and the outflow time. In all cases the correlation coefficients (R-2 values) were very high. Recommendations for additional studies that might be conducted to exploit additional information that can be obtained by processing the CTMeter profiles are made. In particular, the analysis of the directional properties of the surface texture as they may relate to wet pavement friction and tire-pavement noise is suggested.