1、Designation:D442909aStandard Test Method forCBR(California Bearing Ratio)of Soils in Place1This standard is issued under the fixed designation D4429;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number i
2、n parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope*1.1 This test method covers the determination of the Cali-fornia
3、Bearing Ratio(CBR)of soil tested in place by thepenetration load of the soil.This test method covers theevaluation of the relative quality of subgrade soils,but isapplicable to subbase and some base-course materials.This testmethod is designed to test in-situ materials and corresponds toTest Method
4、D1883.1.2 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-conformancewit
5、h the standard.1.2.1 In the engineering profession it is customary to useunits representing both mass and force interchangeably,unlessdynamic calculations are involved.This implicitly combinestwo separate systems of units,that is,the absolute system andthe gravitational system.It is scientifically u
6、ndesirable tocombine the use of two separate sets of inch-pound units withina single standard.This test method has been written using thegravitational system of units when dealing with the inch-poundsystem.In this system,the pound(lbf)represents a unit of force(weight).However,conversions are given
7、in the SI System.The use of balances or scales recording pounds of mass(lbm),or the recording of density in lbm/ft3should not be regarded asnonconformance with this test method.1.3 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPra
8、ctice D6026,unless superseded by this standard.1.3.1 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as theindustry standard.In addition they are representative of thesignificant digits that generally should be retained.The proce-dures used
9、do not consider material variation,purpose forobtaining the data,special purpose studies,or any consider-ation for the users objectives;and it is common practice toincrease or reduce significant digit of reported data to becommensurate with these considerations.It is beyond the scopeof this standard
10、 to consider significant digits used in analysismethods or engineering design.1.4 This standard does not purport to address all of thesafety problems,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determin
11、e the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D653 Terminology Relating to Soil,Rock,and ContainedFluidsD1556 Test Method for Density and Unit Weight of Soil inPlace by Sand-Cone MethodD1883 Test Method for CBR(California Bearing Ratio)ofLabora
12、tory-Compacted SoilsD2167 Test Method for Density and Unit Weight of Soil inPlace by the Rubber Balloon MethodD2216 Test Methods for Laboratory Determination of Water(Moisture)Content of Soil and Rock by MassD2937 Test Method for Density of Soil in Place by theDrive-Cylinder MethodD3740 Practice for
13、 Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD6026 Practice for Using Significant Digits in GeotechnicalDataD6780 Test Method for Water Content and Density of Soil inPlace by Time Domain Reflectometry(TDR)D6938 T
14、est Method for In-Place Density and Water Contentof Soil and Soil-Aggregate by Nuclear Methods(ShallowDepth)1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.08 on Special andConstruction Control Tests.Current editio
15、n approved Dec.1,2009.Published January 2010.Originallyapproved in 1984.Last previous edition approved in 2009 as D4429 09.DOI:10.1520/D4429-09A.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandardsvolum
16、e information,refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.Terminology3.1 DefinitionsAll definitions are in accordance with Ter-minology D653.4.Significance and Use4.1 Field in-place CBR tests are used for evaluation anddesign of flexible pavement components such as base andsubbase course and subgrades
