ASTM_E_1170_-_97_2012.pdf

Designation:E117097(Reapproved 2012)Standard Practices forSimulating Vehicular Response to Longitudinal Profiles ofTraveled Surfaces1This standard is issued under the fixed designation E1170;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 These practices cover the calculation of vehicular re-sponse to longitudinal profiles of traveled surface roughness.1.2 These practices utilize computer simulations to obtaintwo vehicle responses:(1)axle-body(sprung mass)motion or(2)body(sprung mass)acceleration,as a function of time ordistance.1.3 These practices present standard vehicle simulations(quarter,half,and full car)for use in the calculations.1.4 The values stated in SI units are to be regarded as thestandard.1.5 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 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2E950 Test Method for Measuring the Longitudinal Profile ofTraveled Surfaces with an Accelerometer EstablishedInertial Profiling Reference2.2 ISO Standard:2631 Guide for the Evaluation of Human Exposure toWhole-Body Vibration33.Summary of Practices3.1 These practices use a measured profile(see Test MethodE950)or a synthesized profile as part of a vehicle simulation toobtain vehicle response.3.2 The first practice for obtaining vehicle response usessimulation of a quarter-car or half-car model.The output is theaccumulated relative motion between the sprung and unsprungvehicle masses,of the simulated vehicle,for a predetermineddistance.The units are accumulated relative motion per unit ofdistance traveled(m/km or in./mile).For example,the quarter-car simulation is used when a Bureau of Public RoadsBPR/roadmeter is to be simulated,and the half-car model(orthe quarter car with the average of the left and right elevationprofile input)is used when a road meter is to be simulated.3.3 The second practice uses either a quarter-car,half-car,orfull-car simulation to obtain vehicle body acceleration.Theacceleration history can be computed as a function of time ordistance,or both.One application of this practice is to use theacceleration history in a ride quality evaluation,such as theISO Guide 2631.3.4 For all calculations,a vehicle test speed is selected andmaintained throughout the calculation.Pertinent informationaffecting the results must be noted.4.Significance and Use4.1 These practices provide a means for evaluating traveledsurface-roughness characteristics directly from a measuredprofile.The calculated values represent vehicular response totraveled surface roughness.4.2 These practices provide a means of calibrating response-type road-roughness measuring equipment.45.Apparatus5.1 ComputerThe computer is used to calculate accelera-tion and displacement of vehicle response to a traveled surfaceprofile,using a synthesized profile or a profile obtained inaccordance with Test Method E950 as the input.Filtering shallbe provided to permit calculation,without attenuation,atfrequencies as small as 0.1 Hz at speeds of 15 to 90 Km/h(10to 55 mph).Computation may be analog or digital.Noisewithin the computer shall be no more than one quarter of the1These practices are under the jurisdiction of ASTM Committee E17 on Vehicle-Pavement Systems and are the direct responsibility of Subcommittee E17.33 onMethodology for Analyzing Pavement Roughness.Current edition approved June 1,2012.Published May 2013.Originallyapproved in 1987.Last previous edition approved in 2007 as E1170 97(2007).DOI:10.1520/E1170-97R12.2For 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 National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.4Gillespie,T.D.,Sayers,M.W.,and Segel,L.,“Calibration and Correlation ofResponse-Type Road Roughness Measuring Systems,”NCHRP Report 228,1980.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 intended resolution.It is recommended that a 16-bit or betterdigital computer be used.5.2 Data-Storage DeviceA data-storage device shall beprovided for the reading of profiles and the recording andlong-term storage of computed data.Profile data shall be scaledto maintain resolution of 0.025 mm(0.001 in.)and to accom-modate the full range of amplitudes encountered during normalprofile-measuring operations.The device shall not contributeto the recorded data any noi