ASTM E2157-15

1.1 This test method covers the procedure for obtaining and analyzing pavement macrotexture profiles using the Circular Track Meter (CTMeter).

1.2 The CTMeter consists of a charge coupled device (CCD) laser displacement sensor that is mounted on an arm that rotates such that the displacement sensor follows a circular track having a diameter of 284 mm.

1.3 The CTMeter is designed to measure the same circular track that is measured by the Dynamic Friction Tester
(DFTester).

1.4 The CTMeter can be used both for laboratory investigations and in the field on actual paved surfaces.

1.5 The software developed for the CTMeter reports the mean profile depth (MPD) and the root mean square (RMS) values of the macrotexture profiles.

1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.