1、Designation:E241505(Reapproved 2012)Standard Practice forInstalling Piezoelectric Highway Traffic Sensors1This standard is issued under the fixed designation E2415;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revi
2、sion.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 practice covers the installation of piezoelectrictire-force sensors that are used to detect axles when counting,classifying,or
3、weighing vehicles as part of a roadway trafficmonitoring program.Piezoelectric sensors are often used inpairs and combined with other roadway sensors such asinductive loops to classify and weigh vehicles.1.2 The practice applies only to piezoelectric tire-forcesensors used for the detection of vehic
4、le axles on a roadway.1.3 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are for informa-tion only and are not considered standard.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresp
5、onsibility 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:2E867 Terminology Relating to Vehicle-Pavement SystemsE1318 Specification for Highway Weigh-I
6、n-Motion(WIM)Systems with User Requirements and Test MethodsE1442 Practice for Highway-Traffic Monitoring(Withdrawn2001)3E1572 Practice for Classifying Highway Vehicles fromKnown Axle Count and Spacing(Withdrawn 2002)3E1957 Practice for Installing and Using Pneumatic Tubeswith Roadway Traffic Counte
7、rs and Classifiers3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 axleaxis oriented transversely to the nominal direc-tion of vehicle motion and extending the full width of thevehicle,about which the wheels at both ends rotate.3.1.2 axle countnumber of vehicle axles that are en
8、umer-ated at a point on a lane or roadway during a specified timeinterval.3.1.3 axle countera device that receives signals from anaxle sensor and indicates the cumulative number of axles thathave been detected by the sensor during a specified timeinterval.3.1.4 axle spacinghorizontal distance betwee
9、n the centerof a vehicle axle and that of the preceding axle on the vehicle.3.1.5 machinecountcumulativenumberofaxles,vehicles,or vehicles within specified classes,or all of these,indicated or recorded by a traffic recording device for aspecified time interval.3.1.6 traffc counterdevice that indicat
10、es,and usuallyrecords,the number of vehicles or vehicle axles,or both,thatpass a point on a lane or roadway during a specified timeinterval.3.1.7 traffc recording deviceunit that receives outputfrom a sensor(s)and registers axle count,vehicle count,vehicleclassification count,speed,gap,or headway(an
11、y or all ofthese)for defined time intervals.3.1.7.1 DiscussionA traffic recording device may alsorecord axle load and gross-vehicle weight.Refer to Specifica-tion E1318.3.1.8 vehicleone,or multiple,mobile unit(s)designed fortravel upon a roadway;a vehicle comprises one powered unitand may include on
12、e or more non-powered trailer or semitrailerunit(s).3.1.9 vehicle classification countcumulative number ofvehicles of each defined type(class)indicated or recorded fora specified time interval.4.Summary of Practice4.1 Site Selection:4.1.1 Select a relatively straight and smooth section ofroadway tha
13、t is expected to have free flowing traffic throughoutthe duration of the data collection session.4.1.2 The selected roadway section should have little to nosurface distortion or rutting in the wheel paths.1This practice is under the jurisdiction of ASTM Committee E17 on Vehicle-Pavement Systems and
14、is the direct responsibility of Subcommittee E17.52 onTraffic Monitoring.Current edition approved July 1,2012.Published July 2012.DOI:10.1520/E2415-05R12.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStand
15、ards volume information,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.1.3 Longitudinal
16、 grades and lateral pavement slopesshould be less than 3%as per Specification E1318.4.1.4 The selected site should have:4.1.4.1 Access to electrical power or good location for solarand telephone service if data is to be collected continuously formore than a few weeks at a time,4.1.4.2 Adequate space for an instrument cabinet,with asafe area for a technician to park a vehicle and stand whilemaking adjustments or repairs,and4.1.4.3 Adequate drainage to prevent standing water insplice boxes and ins
