ASTM_D_4695_-_03_2020.pdf

Designation:D469503(Reapproved 2020)Standard Guide forGeneral Pavement Deflection Measurements1This standard is issued under the fixed designation D4695;the number immediately following the designation indicates the year oforiginal adoption 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 guide provides procedural information for measur-ing pavement surface deflections,directly under,or at locationsradially outward(offset)from a known static,steady-state,orimpulse load.Deflections are measured with sensors thatmonitor the vertical movement of a pavement surface due tothe load.This guide describes procedures for the deflectionmeasurement using various deflection testing devices andprovides the general information that should be obtainedregardless of the type of testing device used.1.2 This guide is applicable for deflection measurementsperformed on flexible asphalt concrete(AC),rigid portlandcement concrete(PCC),or composite(AC/PCC)pavements.Rigid pavements may be plain,jointed,jointed reinforced,orcontinuously reinforced concrete.1.3 The values stated in SI units are to be regarded asstandard.Inch-pound units given in parentheses are for infor-mation purposes only.1.4 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 environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.5 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 Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D4602 Guide for Nondestructive Testing of Pavements Us-ing Cyclic-Loading Dynamic Deflection EquipmentD4694 Test Method for Deflections with a Falling-Weight-Type Impulse Load DeviceD5858 Guide for Calculating In Situ Equivalent ElasticModuli of Pavement Materials Using Layered ElasticTheory2.2 AASHTO Standard:3T 256 Standard Method of Test for Pavement DeflectionMeasurementsPDDX Pavement Deflection Data ExchangeTechnicalData Guide,Version 1.0,April 19983.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 deflection basin,nthe bowl shape of the deformedpavement surface due to a specified load as depicted from thepeak measurements of a series of deflection sensors placed atradial offsets from the center of the load plate.3.1.2 deflection basin test,na test with deflection sensorsplaced at various radial offsets from the center of the load plate.The test is used to record the shape of the deflection basinresulting from an applied load.Information from this test canbe used to estimate material properties for a given pavementstructure.3.1.3 deflection sensor,nelectronic device(s)capable ofmeasuring the relative vertical movement of a pavementsurface and mounted in such a manner as to minimize angularrotation with respect to its measuring plane at the expectedmovement.Such devices may include seismometers,velocitytransducers,or accelerometers.3.1.4 load cell,ncapable of accurately measuring the loadthat is applied perpendicular to load plate and placed in aposition to minimize the mass between the load cell and thepavement.The load cell shall be positioned in such a way thatit does not restrict the ability to obtain deflection measurementsunder the center of the load plate.The load cell shall be waterresistant,and shall be resistant to mechanical shocks from roadimpacts during testing or traveling.1This guide is under the jurisdiction of Committee E17 on Vehicle-PavementSystems and is the direct responsibility of Subcommittee E17.41 on PavementTesting and Evaluation.Current edition approved Nov.1,2020.Published November 2020.Originallyapproved in 1987.Last previous edition approved in 2015 as D4695 03(2015).DOI:10.1520/D4695-03R20.2For 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.3Available from American Association of State Highway and TransportationOfficials(AASHTO),444 N.Capitol St.,NW,Suite 249,Washington,DC 20001,http:/www.transportation.org.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 issued by the World Trade Organization Technical Barriers to