TCVN 8864 : 2011 Standard Test Method for Measuring Road Pavement Surface Roughness Using a 3.0 m Straight Edge Foreword TCVN 8864: 2011 is changed from 22 TCN 16-79 under the provision of paragraph of Article 69 of the Law on Standards and Technical Regulations and point a of paragraph of Article of Decree No 127/2007/ND-CP dated 01 Aug 2008 of the Government detailing the implementation of some articles of the Law on standards and technical regulations TCVN 8864: 2011 complied by the Institute of Science and Technology Editor of Transportation, proposed by Ministry of Transportation, announced by Directorate for Standards, Metrology and Quality Assessment, Ministry of Science and Technology Standard Test Method for Measuring Road Pavement Surface Roughness Using a 3.0 m Straight Edge Application scope 1.1 This standard defines the sequence of measuring and evaluating road pavement surface roughness as well as surface of each layer structure (base and foundation) of road during construction and acceptance for each road pavement surface section by using 3.0 meter straight edge 1.2 This standard can be used to perform the acceptance for the surface roughness of each section or to evaluate the roughness of road surface during the exploitation process in the absence of a self-propelled roughness measuring mean Test summary At experiment location, place m straight edge on road surface in a direction parallel or perpendicular to the axis of roadway Use a wedge to insert into the gap between road surface and the bottom of the straight edge at measuring points with interval of 50 cm from the beginning of straight edge Identify gaps corresponding to the height of the wedge as a basis to examine and evaluate the roughness of road surface Tool and instrument 3.1 Straight edge: usually made of stainless metal, 3.0 m long Ruler must be straight, lightweight, stiff enough not to be deformed during experiment, and marked with measuring points for measuring interval of 50 cm from the beginning of ruler (Figure 1) 3.2 Wedge: usually made of stainless metal and less abrasive, triangle marking with height values: mm, mm, mm, 10 mm, 15 mm and 20 mm for quickly reading gap value (mm) between road surface and the lower edge of straight edge m (Figure 2) Figure - Wedge 3.3 Broom to wipe road surface, traffic guidance tools (billboards, guidance cone, ) Density Test 4.1 When checking and assessing the roughness during construction and acceptance: perform measurement in each lane, longitudinal direction of the road, minimum 0.6 m away from road edge or curb, with measuring density of 25 meters long / location 4.2 When evaluating the roughness of old road surface under exploitation: perform measurement in each lane, longitudinal direction within the scope of wheel vicious streak subsidence, with measuring density of 50 meters long / location 4.3 In case of necessity, it can measure in the direction perpendicular to the road Perfomance procedure 5.1 Check the straightness of ruler before every time of using Set up traffic guidance tools (billboards, guidance cones,…) at measurement location; use broom to clean road surface at location of roughness measurement 5.2 At each test location on road surface or on surface layer of material, place 3m straight edge parallel to the road Along the length of ruler, at measuring points with interval of 50 cm as determination by ruler, gently insert the wedge into the gap between the bottom edge of the ruler and road surface; Read the corresponding values Total gaps for each measurement is Measurement results are recorded in accordance with the guidance in Appendix A Criteria for roughness evaluation 6.1 Criteria for evaluation, testing and acceptance of roughness are defined in Table 1, and divided into three (3) levels: very good, good and moderate depending on layer location and material of such layer 6.2 When performing test and acceptance for road surface under construction or newly completed one, apply the following evaluation criteria: - For highway, class I road and class II road: the roughness should be very good; - For road of other classes: the roughness should be good; NOTE 1: For all road classes, it is allowable to have 5% of the gaps exceeding the biggest regulated gap value corresponding to the requirement roughness, but the biggest gap value shall not exceed 1.4 times as the corresponding regulated value 6.3 When evaluating the old road surface under exploitation, if the roughness at moderate level, the roughness may be considered to meet exploitation requirement Table - Criteria for roughness evaluation Layer Material of layer Roughness level Very good Good Moderate Top layer and flattened wearing course 70% of the Asphalt concrete, 50% of the measured gaps not 100% of the cement concrete measured gaps not over mm; the measured gaps not and small-sized over mm; the rest 30% not over over mm granular mix rest not over mm mm Base 50% of the 100% of the 100% of the Asphalt concrete, measured gaps not measured gaps not measured gaps not black aggregate over mm; ; the over mm over mm rest not over mm Top layer or flattened wearing course 70% of the Penetration 50% of the 100% of the measured gaps not asphalt and measured gaps not measured gaps not over mm; the bitinuous surface over mm; the rest over mm rest not over 10 treatment not over 10 mm mm 70% of the Top foundation and 100% of the measured gaps not 100% of the Soil, reinforced measured gaps not over 10 mm; the measured gaps not reinforced edge rock; macadam (fixed edge) over 10 mm rest not over 15 over 15 mm aggregate, natural mm aggregate; Water 70% of the bound macadam; Bottom foundation, improved soil, filled 100% of the measured gaps not 100% of the pavement base, measured gaps not over 15 mm; the measured gaps not soil soil base, soil edge over 15 mm rest not over 20 over 20 mm mm Test Report Test report should include the following information: - The name of the road, station, the length of test section; - Type road surface (foundation); - Test date; - Measurement results (see Appendix A); - Tester and test facilities APPENDIX A (for reference) Roughness measuring result by m straight edge - Road name: ……………… - Direction: ………………………… - Road surface type: ………… - Station: From km…to Km…… - Climate at measurement:…………… - Test date: …./…./20… - Tester: ……… - Reviewer: ………………… - Measurement results: Measuring location Gap number between road surface and m straight edge, x Remark (mm) By road axle No Station < x5 < x < x Lane Right Left ParallelPerpendicularx ≤ No ≤ ≤ ≤ 10 Km 35 + 000 Lane x Lane 2 10 < 15 < x ≤ x ≤ > 20 15 20 x … x Lane x Km 35 + 025 x Lane … x x x x Total Percentage (%) Result: Roughness level:…………………………… CONTENT Application scope Test summary Tool and instrument Density Test Performance procedure Criteria for roughness evaluation Test Report APPENDIX A (for reference): Roughness measuring result by m straight edge