1、Designation:E2380/E2380M15Standard Test Method forMeasuring Pavement Texture Drainage Using an OutflowMeter1This standard is issued under the fixed designation E2380/E2380M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of
2、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 connectivity of the textureas it relates to the drainage capability of the pavement throughits
3、 surface and subsurface voids.This is a specific device thattimes how long it takes a known quantity of water,undergravitational pull,to escape through voids in the pavementtexture of the structure being tested.The technique is intendedto provide a measure of the ability of the pavement to relievepr
4、essure from the face of vehicular tires and thus an indicationof hydroplaning potential under wet conditions.Afaster escapetime indicates a thinner film of water may exist between the tireand the pavement,thus more micro-texture could be exposed toindent the face of the tire and more surface frictio
5、n available tothe tire.The lower the number of seconds it takes to evacuatethe water,the lower the water pressure under the tire.It will beup to the operator to compare the results of this test to otherpertinent factors such as expected rainfall intensity andfrequency,aggregate type,consistency of t
6、exture,grade,slope,expected vehicular speed,and accident history,to determinethe relationship between the outflow meter reading and thelikelihood of hydroplaning on a given surface.Comparing theoutflow meter reading of a pavement known to have a historyof hydroplaning,against one with a good history
7、,with all otherfactors similar,will give the operator an indication of theoutflow meter number that will be necessary to promote wetweather safety.1.2 The results obtained using this test method are related tothe mean hydraulic radius of a paved surface and may correlatewith other methods to measure
8、 texture.1.3 The results obtained using this test method are related tothe mean texture depth(MTD).1.4 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 ind
9、ependently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.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
10、 health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2E178 Practice for Dealing With Outlying ObservationsE867 Terminology Relating to Vehicle-Pavement SystemsE965 Test Method for Measuring Pavement MacrotextureDepth Using
11、 a Volumetric Technique(Withdrawn 2015)3E1845 Practice for Calculating Pavement MacrotextureMean Profile DepthE2157 Test Method for Measuring Pavement MacrotextureProperties Using the Circular Track Meter3.Terminology3.1 For definitions of terms,see Terminology E867.4.Summary of Test Method Operatio
12、ns4.1 The main body of the outflow meter is a verticalcylinder for containing water.It has an open top and a rubberring mounted centrally around an orifice or opening on thebottom of the device to form a seal against the pavementsurface.Water discharge is through the opening in the center ofthe seal
13、 and is controlled by a spring-loaded plunger suspendedfrom a cap mounted on the upper end of the cylinder.Upperand lower float switches are suspended from the cap into thecylinder and mounted vertically.An electronic timer is pro-vided and is wired to the float switches.4.2 The outflow meter is pla
14、ced on the pavement with theplunger sealing the water discharge opening.Sufficient water is1This test method is under the jurisdiction of ASTM Committee E17 on Vehicle-Pavement Systems and is the direct responsibility of Subcommittee E17.23 onSurface Characteristics Related to Tire Pavement Slip Res
15、istance.Current edition approved Jan.1,2015.Published January 2015.Originallyapproved in 2005.Last previous edition approved in 2009 as E2380/E2380M 09.DOI:10.1520/E2380_E2380M-15.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.Fo
16、r Annual Book of ASTMStandards 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 then poured into the cylinder to raise the switch floats to theirraised or top position,which will prevent the timer fromoperating.The timer is reset to zero and the plunger is releasedto allo