Nordic certification system for road marking materials

Transcription

1 VTI PM Diarienummer: 2015/ Nordic certification system for road marking materials Results of initial performance measurements at the Danish test site 2015 Carina Fors Trond Cato Johansen

2

3 Preface A Nordic certification system for road marking materials was introduced in In the first stage, the certification system applies to the countries of Denmark, Norway and Sweden. In these countries, a documented product approval will be required in order to use a road marking material on roads managed by the national road authorities. Product approval will be based on monitored and documented performance measurements of material samples applied on test fields on public roads. A test field was established in Hornbaek, Denmark, in October This test field will be the basis for product approval in Denmark. The present report documents the results of the initial performance measurements taken shortly after application. The results show whether the materials qualify for continued participation in the road trials. The road trials are administered by Trond Cato Johansen at Ramböll and Carina Fors at VTI. Contact person at the Danish Road Directorate is Kenneth Kjemtrup. Performance measurements were carried out by operators from Ramböll. Linköping, December 2015 Carina Fors VTI PM

4 VTI PM

5 Table of content Abstract Introduction Measurements General Methods and measuring instrument Thickness measurements Retroreflection R L and luminance coefficient Qd Chromaticity coordinates Friction Weather conditions Performance requirements Performance parameters and requirements Special considerations due to the weather conditions Results White materials...16 References...18 VTI PM

6 VTI PM

7 Abstract Nordic certification system for road marking materials Results of initial performance measurements at the Danish test site 2015 by Carina Fors (VTI) and Trond Cato Johansen (Ramböll) This report documents the results of the initial performance measurements at the Danish test site In total, 32 materials were applied at the test field. 24 participated as certification materials while 8 were test materials. Performance measurements of coefficient of retroreflected luminance R L, luminance coefficient under diffuse illumination Qd, chromaticity in daylight, and friction were carried out approximately two weeks after applications. The aim of these measurements was to determine whether the materials qualify for continued participation in the road trials. Out of the 24 certification materials, 17 were approved for continued participation. One material was disqualified because the requirement on retroreflection R L was not fulfilled. Five materials were disqualified because the requirement on friction was not fulfilled. For one material, two lines were disqualified at application because the requirement on thickness was not fulfilled. One material was excluded because the participant fee was not paid. VTI PM 7

8 8 VTI PM

9 1. Introduction A Nordic certification system for road marking materials was introduced in In the first stage, the certification system applies to the countries of Denmark, Norway and Sweden. In these countries, a documented product approval will be required in order to use a road marking material on roads managed by the national road authorities. Product approval will be based on monitored and documented performance measurements of material samples applied on test fields on public roads. The certification system includes two test sites: one in Sweden (for product approval in Sweden and Norway) and one in Denmark (for product approval in Denmark). The first round of material tests in Denmark started in October 2015, when 32 materials were applied at the Danish test site in Hornbaek. The present report documents the results of the application and of the initial performance measurements that were carried out shortly after application. At the application, the materials were examined with respect to material thickness and geometrical requirements. The performance measurements included coefficient of retroreflected luminance R L, luminance coefficient under diffuse illumination Qd, chromaticity in daylight and friction. The aim of the initial examination and measurements was to determine whether the materials qualify for continued participation in the road trials. Follow-up measurements will be carried out only on materials that are approved at the initial measurements. No material certification will be given based on the initial measurements (i.e. the results presented in this report). Certification will be given based on the results at the follow-up measurements in 2016 and The report includes results of materials registered as certification materials. Results of materials registered as test materials will be available only to the supplier. The certification system is further described in the document Nordic certification system for road marking materials Version 2:2015 (Fors, Johansen and Lundkvist, 2015). The document is referred to as NCSRM-2:2015. VTI PM 9

10 2. Measurements 2.1. General The performance measurements of retroreflection R L, luminance coefficient Qd, chromaticity coordinates and friction were carried out days after application. Measurements of retroreflection, luminance coefficient, chromaticity coordinates and friction were carried out by operators from Ramböll, supervised by an observer from VTI. All measurement equipment were calibrated according to recommended procedures provided by the respective instrument manufacturer Methods and measuring instrument Thickness measurements The thickness of the applied materials was measured immediately after application. When applying the lines, material was applied also on two steel plates that were placed in the end of two of the six lines. One of the plates were applied with drop on material, and the other without any drop on. The plates were weighed before and after application. The thickness was measured from the plate without drop on, and also controlled by the weight of the material on the plate. Additional thickness controls were carried out directly on several of the marking lines, as applied on the trials Retroreflection RL and luminance coefficient Qd The coefficient of retroreflected luminance, R L, and the luminance coefficient under diffuse illumination, Qd, were measured using an LTL-XL (Delta, Denmark). Measurements were taken at three points diagonally within the measurement area defined by EN 1824, Figure 1. The result of an individual line was calculated as the average of the three measurements. Figure 1. The measurement points (red crosses) for R L and Qd were placed diagonally within the measurement area (grey) defined by EN The markings were not cleaned before the measurements, but in case a substantial part of the measurement area was abnormally dirty (e.g. oil stain), the instrument was moved in the longitudinal direction to the closest area not affected by abnormal dirt. 10 VTI PM

11 Chromaticity coordinates Chromaticity coordinates were measured in one point on each line, located at the centre of the line, Figure 2. A Konica Minolta Spectrophotometer CM-2500c was used to measure the colour coordinates. Figure 2. The measurement points (blue crosses) for chromaticity coordinates were placed in the centre of the lines. For materials that had a very non-homogenous surface (due to unevenly distributed drop-on), an area that appeared to represent the average surface of the material was selected as measurement point. In some cases several measurement points were selected, to ensure correct chromaticity coordinates. These points had to be located within the grey area in Figure 2. The markings were not cleaned before the measurements, but in case a substantial part of the measurement area was abnormally dirty (e.g. oil stain), the instrument was moved to the closest area not affected by abnormal dirt Friction Friction measurements were carried out using a Portable Friction Tester version 4 (PFT), along the centre of each line, Figure 3. The PFT takes a sample approximately every 1.9 cm and thus, about 70 samples are taken on each line. The result of an individual line is calculated as the average of all samples from that line. In case there were any notches, joints or other abnormalities on the marking surface, the measurement area/line was either reduced or moved somewhat, so that no samples were taken from the abnormality. The PFT instrument is further described in (Wälivaara 2007). VTI PM 11

12 Figure 3. The measurement areas (green lines) for friction Weather conditions The test field was established in October, and the performance measurements thus had to be carried out in the late autumn, when the weather conditions are not optimal. During the weeks following application, the weather was changeable, with dry days mixed with rain and fog. In order to be able to accomplish the performance measurements according to the time plan, the requirement on dry weather and dry markings could not always be met. The strategy used for evaluating moist markings is described in Section 3.2. During the measurements of retroreflection R L, luminance coefficient Qd and chromaticity coordinates, the air temperature was 7 12 C, the temperature of the road marking surface was approximately 10 C and the relative humidity was %. The temperature of the road marking surface was sometimes below the dew point (according to the dew point table in EN 1824). During the measurements of friction, the air temperature was 8 10 C and the temperature on the road marking surface was approximately 10 C. The markings had a slightly moist surface due to the weather. If needed, water was sprayed on the surface to make it wet enough for the friction measurements. 12 VTI PM

13 3. Performance requirements 3.1. Performance parameters and requirements The performance requirements of the four parameters are given in Table 1. Table 1. Performance requirements. Performance parameter White markings Coefficient of retroreflected luminance, RL dry [mcd/m 2 /lx] 150 Luminance coefficient under diffuse illumination, Qd [mcd/m 2 /lx] 130 Friction, [PFT units] 0.52 Chromaticity coordinates, x, y * *) According to EN 1436 The measurement results from the six lines were averaged, and compared to the performance requirements in Table 1. The results of individual lines have been stored, but were not further evaluated. In order for a material to be approved for continued participation, all four performance parameters must fulfil the requirements. Regarding the requirements on thickness and geometry, individual lines were disqualified if they didn t fulfil the requirements. The reason for evaluating R L, Qd, friction and chromaticity coordinates based on the average of the six lines at the initial measurement, but evaluating thickness and geometry for individual lines is that the four former represent the properties of the material and the most representative data on these properties is the average of all measurements taken. This goes only for the initial measurement, as there is no wear caused by traffic impact at this point of time. But for thickness and geometry, all individual lines must fulfil the requirement, since at the follow-up measurement the performance is evaluated for different P classes, where one or a few lines may represent a certain P class. The performance of a single line will then have a large impact on the result, and in case it was too thick at application, this will give unfair results. This however implies that, for material where one or more lines were disqualified because they didn t fulfil the requirements on thickness and geometry, there is a risk that these materials cannot be evaluated and certified for certain P classes 1.` 3.2. Special considerations due to the weather conditions Because of the weather conditions (see Section 2.3) some modifications had to be made regarding the measurement procedures and the performance requirements. In case a material had a slightly moist surface and did not fulfil the requirements on retroreflection R L, the material was dried by a hand-held leaf blower until the performance requirement was met. This implies that the reported R L values probably are underestimated for these materials (marked with an in the result table). 1 Measurements of wheel passages will be carried out in VTI PM 13

14 There was some dirt from fallen leaves, particularly on the lines closest to the right edge of the roadway and on the lines with most wheel passages (lines 1, 2, and 5). This had no significant influence on the results regarding retroreflection R L, luminance coefficient Qd or colour coordinates, since all materials (except one 2 ) fulfilled the requirements on these parameters. It could however not be ruled out that the dirt had an influence on the friction measurements. In order to investigate this potential influence, the friction of the dirtiest line (line 2) was compared to that of the least dirty line (line 4). On average, the friction was 0.01 units higher on the least dirty line than on the dirtiest line. The difference was not significant (t test, significance level α = 0.05) and it was in agreement with the difference in friction between the corresponding lines on the Swedish test site, where no dirt was present. Four of the dirtiest materials were assessed individually. For all these four materials, friction was either identical on the dirtiest line and the least dirty line, or somewhat higher on the dirtiest line. In addition to the potential influence of dirt, the poor weather conditions might have had an influence on the friction measurements. The method description for the PFT instrument prescribes an air temperature of at least 5 C and recommends a surface temperature in the interval of C. The surface temperature was unfortunately somewhat lower than recommended (approximately 10 C). The influence of temperature has been investigated for a previous version of the PFT instrument, where it was estimated that the difference in friction when the temperature (air and surface) was 5 C and 20 C, respectively, was in the range of ±0.04 units (Åström 2001). That is, friction may be influenced by the temperature, but there is no clear relationship. The friction of some materials may decrease somewhat if the temperature decreases, while the friction of other material may increase or remain constant. In order to eliminate the risk that materials are rejected because of the possible influence of temperature or dirt on the friction measurements, the required limit for approval was lowered by 0.05 units, from 0.52 to This requirement adjustment goes for this measurement only, as the weather conditions were unfortunate in the late fall. 2 One material was disqualified because the requirement on retroreflection R L was not fulfilled (for any of the six lines). In this case, the poor performance was due to an unsuccessful application and thus not caused by dirt. 14 VTI PM

15 4. Results The table in Section 4.1 show the results of the initial measurements of retroreflection R L, luminance coefficient Qd, friction, chromaticity coordinates, and thickness for all materials registered and applied as certification materials, at the Danish test site in Hornbaek In total, 24 materials participated as certification materials. Out of these 24 materials, 17 were approved for continued participation. One material was disqualified because the requirement on retroreflection R L was not fulfilled. Five materials were disqualified because the requirements on friction were not fulfilled. For one material, two lines were disqualified at application because the requirement on thickness was not fulfilled. One material was excluded because the participant fee was not paid. Explanation of the columns in the result tables RL Qd Friction Colour Thickness Disq. lines Approved Mean value of coefficient of retroreflected luminance RL [mcd/m 2 /lx] Mean value of luminance coefficient under diffuse illumination Qd [mcd/m 2 /lx] Mean value of friction [PFT units] Approved (A) or Not Approved (NA) chromaticity coordinates Material thickness [mm] Lines that were disqualified at application (too thick, wrong size or missing) Approved (A) or Not Approved (NA) for continued participation. A* = one or more lines are disqualified. Values that do not fulfil the performance requirements are indicated in orange. Note: the performance requirement on friction was lowered from 0.52 to 0.47 PFT units in order to eliminate the risk that materials are rejected because of the potential influence of low temperature and dirt (see also Section 3.2). Note: since there was a slight moisture on the surface of some of the materials when the measurements were carried out (marked with an in the result table), the coefficient of retroreflected luminance R L of these materials are probably higher than what is presented below (see also Sections 2.3 and 3.2). VTI PM 15

16 4.1. White materials Supplier Material name R L Qd Friction Colour Thickness Disq. lines Approved Ennis Flint (Prismo road mark. Ltd) Lifeline LL A 3.0 NA Ennis Flint (Prismo road mark. Ltd) EF Series Preformed Thermoplastic Material A 2.9 NA Ennis Flint (Prismo road mark. Ltd) Lifeline LL A 2.5 NA Ennis Flint (Prismo road mark. Ltd) EF Series Preformed Thermoplastic Material A 3.2 A Ennis Flint (Prismo road mark. Ltd) Crystalex A 2.7 NA Hitex Traffic Safety Limited HiBrite WR Extr DK # A 3.1 NA Hitex Traffic Safety Limited HiBrite WR Extr DK # A 3.1 NA Kelly Bros (Erinline) Ltd Kelly Bros (Erinline) Ltd Kelly Bros (Erinline) Ltd Kelly Bros (Erinline) Ltd Extr./Screed Briteline 150(DK) - WE 150 Type 1 (DK) Extr./Screed Briteline 150(DK) - WE 150 Type 2 (DK) White Spray Briteline 150(DK) - WS 150 Type 2 (DK) White Spray Briteline 150(DK) - WS 150 Type 1 (DK) A 2.9 A A 3.0 A A 1.7 A A 1.7 A LKF Materials A/S PREMARK A 3.1 A LKF Materials A/S Viatherm Viking A 2.7 A LKF Materials A/S Viatherm DK A 2.5 2, 3 A* LKF Materials A/S Viatherm DK A 3.1 A LKF Materials A/S Viatherm DK A 2.0 A Promax Industries ApS Promax white basic DK A 2.6 A Sikker På Vej ApS GL E150 (VD) NA** ) Moist surface. RL is probably higher than the value presented. *) One or more lines are disqualified. **) No payment received. 16 VTI PM

17 Supplier Material name R L Qd Friction Colour Thickness Disq. lines Approved Swarco Vestglas Gmbh Eurotherm HPX A 3.0 A Swarco Vestglas Gmbh Swarcotherm ERP 15 white DK A 2.4 A Svevia AB E A 2.6 A Svevia AB E A 2.9 A Veluvine BV Thermolit Lolland A 3.0 A Veluvine BV Thermolit Funen A 2.9 A ) Moist surface. RL is probably higher than the value presented. VTI PM 17

18 References Fors, C., Johansen, T-C. and Lundkvist, S-O. (2015). Nordic certification system for road marking materials Version 2:2015. VTI notat in press. Swedish National Road and Transport Research Institute, Linköping, Sweden. Wälivaara, B. (2007). Validering av VTI-PFT version 4. Mätningar på plana och profilerade vägmarkeringar. VTI notat Swedish National Road and Transport Research Institute, Linköping, Sweden. Åström, H. (2001). Validering av VTI PFT version 3. VTI notat Swedish National Road and Transport Research Institute, Linköping, Sweden. 18 VTI PM