Surface irregularities measured by static device

The surface irregularities in the longitudinal and, mainly, in the transverse direction (rut depth) may be measured by a simple static apparatus known as straightedge. 

Measurements are made to ascertain the greatest distance between the straightedge and the surface to be measured and are recorded to the nearest 1 mm. 

The test procedure is carried out by CEN EN 13036-7 (2003), ASTM E 1703 (2010) or other national specifications. 

This test method is not applicable to providing information on profile or general unevenness and the rut depth value obtained may not correlate well with values obtained using 

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