1、Designation:E217719Standard Test Method forMeasuring the Coefficient of Retroreflected Luminance(RL)of Pavement Markings in a Standard Condition of Wetness1This standard is issued under the fixed designation E2177;the number immediately following the designation indicates the year oforiginal adoptio
2、n or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the measurement of the wetretroreflective(RL)properties of
3、 horizontal pavement markingmaterials,such as traffic stripes and road surface symbols,using a portable or mobile retroreflectometer that can be placedon or before the road marking to measure the retroreflection atthe prescribed geometry.1.2 This method of measuring the wet retroreflective prop-erti
4、es(RL)of pavement markings measures the wet retroreflec-tivity in a standard condition of wetness(see Fig.1).1.2.1 DiscussionThis test condition typically exists(1)after a rainfall has ended and the pavement markings are stillwet or(2)as the markings are wet from dew or humidity.1.3 Retroreflective
5、performance obtained with this test inconditions of wetness does not necessarily relate to howmarkings perform in conditions of rain,that is,as markings arebeing rained upon.Test Method E2832 defines a method tomeasure the performance of pavement markings in conditionsof simulated rain.1.4 This test
6、 method specifies the use of portable or mobilereflectometers that can measure pavement markings in accor-dance with Test Method E1710.2The entrance and observationangles required of the retroreflectometer in this test method arecommonly referred to as“30 meter geometry.”21.5 The values stated in SI
7、 units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and envi
8、ronmental practices and deter-mine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standa
9、rds,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:3E177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Pre
10、cision of a Test MethodE965 Test Method for Measuring Pavement MacrotextureDepth Using a Volumetric TechniqueE1710 Test Method for Measurement of RetroreflectivePavement Marking Materials with CEN-Prescribed Ge-ometry Using a Portable RetroreflectometerE2832 Test Method for Measuring the Coefficient
11、 of Ret-roreflected Luminance of Pavement Markings in a Stan-dard Condition of Continuous Wetting(RL-2)2.2 Other Standard:CENEN 1436 Road Marking MaterialsRoad MarkingPerformance for Road Users and Test Methods43.Terminology3.1 coeffcient of retroreflected luminance,RL,nthe ratioof the luminance,L,o
12、f a projected surface to the normalilluminance,E,at the surface on a plane normal to the incidentlight,expressed in candelas per square meter per lux(cd/m2/lx1).Because of the low luminance of pavement markings,theunits commonly used are millicandelas per square meter perlux(mcd/m2/lx).1This test me
13、thod is under the jurisdiction of ASTM Committee E12 on Colorand Appearance and is the direct responsibility of Subcommittee E12.10 onRetroreflection.Current edition approved Jan.1,2019.Published February 2019.Originallyapproved in 2001.Last previous edition approved in 2018 as E2177 18.DOI:10.1520/
14、E2177-19.2Reference ASTM E1710“Standard Test Method for Measurement of Retrore-flective Pavement Markings with CEN-Prescribed Geometry Using a PortableRetroreflectometer.”The standard measurement condition is intended to representthe angles corresponding to a distance of 30 m for the driver of a pas
15、senger car withan eye height of 1.2 m and a headlight height of 0.65 m above the road.SeeAppendix X1.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Docume
16、nt Summary page onthe ASTM website.4Available from European Committee for Standardization(CEN),36 rue deStassart,B-1050,Brussels,Belgium,http:/www.cenorm.be.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations is
