Measurement of texture depth by volumetric technique

This method was formerly known as the sand patch method. The name changed after the introduction of fine glass spheres instead of fine sand. The test procedure is carried out by CEN EN 13036-1 (2010) of ASTM E 965 (2006). 

Texture depth directly affects the skid resistance of the pavement surface. In many countries, the minimum allowed texture depth is 0.5 mm. Pavement segments with values lower than 0.5 mm should be investigated immediately, along with skid resistance measurements, and restoration of the surface skid resistance should be programmed. 

Minimum surface texture depth is also required after completion of asphalt works. The minimum values required depend on the type of asphalt used in surfacing. In the case of new asphalt layer with asphalt concrete for very thin layers (AC-VTL), the minimum MTD usually required is 1.00 mm in addition to that, no individual value should be less than 0.8 mm. 

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