ASTM_E_2340_-_E_2340M_-_11_2015.pdf

Designation:E2340/E2340M11(Reapproved 2015)Standard Test Method forMeasuring the Skid Resistance of Pavements and OtherTrafficked Surfaces Using a Continuous Reading,Fixed-SlipTechnique1This standard is issued under the fixed designation E2340/E2340M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the measurement of the skidresistance of a pavement or other trafficked surface using thecontinuous reading,fixed-slip technique.1.2 This test method covers braked wheel measurementsobtained with less than 100%slip.It does not cover side forcemeasurements.1.3 This test method provides a record of the skid resistancealong the whole length of one track of the test surface andenables averages to be obtained for specified test segments.1.4 This test method is used to measure skid resistance on awide variety of surfaces in a wide variety of circumstances.Consequently,there are many different designs of continuousreading,fixed-slip measuring equipment(CFME)and as manydifferent test procedures governing their use.1.5 This test method does not attempt to detail thesedifferent equipments and procedures but does set out theessential common principles.1.6 CFMEs function by creating and measuring a frictionalforce between a test tire operating at a selected slip and the testsurface.Different types of CFME do not necessarily create thesame frictional force between their particular test tire and acommon test surface and do not necessarily use the samemethod to measure this frictional force.1.7 CFME measurements are obtained at a selected steadytest speed.This speed may vary according to the application.1.8 The test surface may be contaminated or clean and dry.If it is clean and dry,a measured amount of water is normallydeposited on the surface just in front of the test wheel.1.9 The measuring apparatus may be built into a vehicle,built into a trailer that is towed by a vehicle,or built into adevice that is manually pushed.1.10 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.1.11 This standard may involve hazardous materials,operations,and equipment.This standard does not purport toaddress all of the safety concerns,if any,associated with itsuse.It is the responsibility of the user of this standard toestablish appropriate safety and health practices and deter-mine the applicability of regulatory limitations prior to use.Safety precautionary information is contained in Section 7.2.Referenced Documents2.1 ASTM Standards:2E178 Practice for Dealing With Outlying ObservationsE501 Specification for Rib Tire for Pavement Skid-Resistance TestsE524 Specification for Smooth Tire for Pavement Skid-Resistance TestsE867 Terminology Relating to Vehicle-Pavement SystemsE1551 Specification for Special Purpose,SmoothTreadTire,Operated on Fixed Braking Slip Continuous FrictionMeasuring EquipmentE1844 Specification forASize 10 45 Smooth-Tread Fric-tion Test TireF408 Test Method for Tires for Wet Traction in Straight-Ahead Braking,Using a Towed TrailerF457 Test Method for Speed and Distance Calibration ofFifth Wheel Equipped With Either Analog or DigitalInstrumentation3.Terminology3.1 For definitions of terms used in this test method,refer toTerminology E867.1This test method is under the jurisdiction of ASTM Committee E17 on Vehicle-Pavement Systems and is the direct responsibility of Subcommittee E17.21 onField Methods for Measuring Tire Pavement Friction.Current edition approved Sept.1,2015.Published December 2015.Originallyapproved in 2006.Last previous edition approved in 2011 as E2340/E2340M 111.DOI:10.1520/E2340_E2340-11R15.2For 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 Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2 Definitions:3.2.1 braking force,ndynamic instantaneous frictionalforce acting on the test wheel.3.2.2 braking force coeffcient(BFC),nappropriately fil-tered mean of a number of instantaneous friction readings overa defined distance.3.2.3 braking slip friction,ntangential force generatedbetween the test tire and the test surface.3.2.4 braking slip ratio,nratio of relative braking slipcircumferential speed to identical unbraked wheel circumfer-ential speed,usually defined as a percent.3.2.4.1 DiscussionAn equivalent definition is the ratio ofthe relative