Standard Test Method for Measurement of Retroreflective Pavement Marking Materials Using a Mobile Retroreflectometer Unit (MRU)

Importancia y uso:

5.1 The quality of the pavement marking is determined by the coefficient of retroreflected luminance, R_L, and depends on the materials used, age, wear pattern, application method, pavements surface, and other conditions.

5.2 Under the same conditions of illumination and viewing, larger values of R_L correspond to higher levels of visual performance in dark conditions.

5.3 Retroreflectivity of pavement (road) markings degrades with traffic wear and requires periodic measurement to ensure that sufficient line visibility is provided to drivers.

5.4 MRUs are used to measure R_L values of road markings while moving at traffic speed, and can be used for longer stretches of road than portable instruments and in cases where the use of portable instruments require extensive precautions, in particular on motorways.

5.5 The measurement geometry of the MRU is based on a viewing distance of 30 m, a headlight mounting height of 0.65 m directly over the stripe, and an eye height of 1.2 m directly over the marking according to CEN 1436 and Test Method E1710.

5.6 MRUs are to be calibrated, maintained, and operated according to instructions by the instrument supplier or manufacturer.

5.7 It shall be the responsibility of the user to employ an MRU fulfilling the required specifications in this standard.

Subcomité:

E12.10

Volúmen:

06.01

Número ICS:

93.080.20 (Road construction materials)

Palabras clave:

horizontal pavement markings; mobile retroreflectometer unit; pavement markings; retroreflectivity; surface symbols; traffic stripes;