1、Designation:D3744/D3744M11aStandard Test Method forAggregate Durability Index1This standard is issued under the fixed designation D3744/D3744M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.A number in pare
2、ntheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of a durabilityindex of an aggregate.The calculated durability index is avalue indicating the relative resistan
3、ce of an aggregate toproduction of detrimental clay-like fines when subjected to theprescribed mechanical methods of degradation.1.2 UnitsThe values stated in either SI units or inch-pound units are to be regarded separately as standard.Thevalues stated in each system may not be exact equivalents;th
4、erefore,each system shall be used independently of the other.Combining values from the two systems may result in non-conformance with the standard.1.2.1 Measurements of volume and mass are only given inSI units because they are the only units typically used inpractice when performing this test metho
5、d.1.2.2 Measurements in Section 11,Section 15,Equation 3,Equation 4,Table 1,and Figure 2 are only given in inch-poundunits because the equipment used in these sections is onlymanufactured using the inch-pound system.1.3 This standard does not purport to address all of thesafety concerns,if any,assoc
6、iated 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:2C127 Test Method for Relative Density(Specific Gravity)and A
7、bsorption of Coarse AggregateC136 Test Method for Sieve Analysis of Fine and CoarseAggregatesC702 Practice for Reducing Samples ofAggregate to TestingSizeD75 Practice for Sampling AggregatesD2419 Test Method for Sand Equivalent Value of Soils andFine AggregateD3666 Specification for Minimum Requirem
8、ents for Agen-cies Testing and Inspecting Road and Paving MaterialsD4753 Guide for Evaluating,Selecting,and Specifying Bal-ances and Standard Masses for Use in Soil,Rock,andConstruction Materials TestingE11 Specification for Woven Wire Test Sieve Cloth and TestSieves3.Summary of Test Method3.1 This
9、test method was developed to permit prequalifica-tion of aggregates proposed for use in the construction oftransportation facilities.Basically,the test establishes an ag-gregates resistance to generating fines when agitated in thepresence of water.Separate and different test procedures areused to ev
10、aluate the coarse and the fine portions of a material.3.2 A sample of coarse aggregate is prepared to a specificgrading and then washed in a mechanical washing vessel for a2-min agitation time.After discarding the minus 4.75-mm(No.4)material,dry the washed test sample.3.3 The coarse aggregate test s
11、ample is then agitated in themechanical washing vessel for a period of 10 min.A represen-tative portion of the resulting wash water and minus 75-m(No.200)size fines is collected and mixed with a stockcalcium chloride solution and placed in a plastic cylinder.Aftera 20-min sedimentation time,the leve
12、l of the sediment columnis read.The height of the sediment value is then used tocalculate the durability index of the coarse aggregate(Dc).3.4 The fine aggregate sample is prepared by washing aspecific quantity of the material in the mechanical washingvessel for a 2-min agitation period.All minus 75
13、-m(No.200)size material is washed from the sample through a 75-m(No.200)sieve and discarded.The plus 75-m(No.200)fraction isdried.3.5 The fine aggregate test sample is tested by the StandardSand Equivalent Test Method(Test Method D2419)except formodifications to the test sample preparation and durat
14、ion of theshaking time.The mechanical shaker method is required.Ashaking time of 10 min instead of 45 s is used.3.6 This test method includes procedures for testing aggre-gates exhibiting a wide range in specific gravity,including1This test method is under the jurisdiction of ASTM Committee D04 on R
15、oadand Paving Materials and is the direct responsibility of Subcommittee D04.51 onAggregate Tests.Current edition approved Dec.1,2011.Published December 2011.Originallyapproved in 1979.Last previous edition approved in 2011 asD3744 11.DOI:10.1520/D3744_D3744_D3744M11A2For referenced ASTM standards,v
16、isit 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 lightweight and porous coarse aggregates,and also proceduresfor testing small maximum size aggregate which is too fine totest as a coarse aggregate and too coarse to consider as a fineaggr
