1、Designation:D692810Standard Test Method forResistance of Coarse Aggregate to Degradation by Abrasionin the Micro-Deval Apparatus1This standard is issued under the fixed designation D6928;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revisio
2、n,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 This test method covers a procedure for testing coarseaggregate for resistance to abrasion using the Micro-De
3、valapparatus.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 The text of this method references notes and footnoteswhich provide explanatory material.These notes and footnotes(excluding those in tables and figures)shall n
4、ot be consideredas requirements of the test method.1.4 This procedure may involve hazardous materials,operations,and equipment.This standard does not purport toaddress all of the safety concerns,if any,associated with itsuse.It is the responsibility of the user of this standard toestablish appropria
5、te safety and health practices and deter-mine the applicability of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2C136 Test Method for Sieve Analysis of Fine and CoarseAggregatesC670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction
6、MaterialsE11 Specification for Woven Wire Test Sieve Cloth and TestSieves3.Terminology3.1 Definitions:3.1.1 constant mass,nthe condition of a test sample driedat a temperature of 110 6 5C such that it will not lose morethan 0.1%moisture after 2 h of drying.3.1.1.1 DiscussionSuch a condition of dryne
7、ss can beverified by determining the mass of the sample before and aftersuccessive 2-h drying periods.In lieu of such a determination,samples may be considered to have reached constant masswhen they have been dried at a temperature of 110 6 5C foran equal or longer period than that previously found
8、adequatefor producing the desired constant mass condition under equalor heavier loading conditions of the oven.4.Summary of Test Method4.1 The Micro-Deval Test is a measure of abrasion resis-tance and durability of mineral aggregates resulting from acombination of actions including abrasion and grin
9、ding withsteel balls in the presence of water.A sample with standardgrading is initially soaked in water for not less than one hour.The sample is then placed in a jar mill with 2.0 L of water andan abrasive charge consisting of 5000 g of 9.5-mm diametersteel balls.The jar,aggregate,water,and charge
10、are revolved at100 rpm for up to 2 h,depending on the particle size.Thesample is then washed and oven dried.The loss is the amountof material passing the 1.18-mm sieve expressed as a percentby mass of the original sample.5.Significance and Use5.1 The Micro-Deval abrasion test is a test of coarseaggr
11、egate to determine abrasion loss in the presence of waterand an abrasive charge.Many aggregates are more susceptibleto abrasion when wet than dry,and the use of water in this testincorporates this reduction in resistance to degradation incontrast to some other tests,which are conducted on dryaggrega
12、te.The test results are helpful in evaluating thetoughness/abrasion resistance of coarse aggregate subject toabrasion when adequate information is not available fromservice records.5.2 The Micro-Deval abrasion test is useful for detectingchanges in properties of aggregate produced from an aggregates
13、ource as part of a quality control or quality assurance process.6.Apparatus6.1 Micro-Deval Abrasion Machine,a jar rolling mill ca-pable of running at 100 6 5 rpm(Fig.1).NOTE1Micro-Deval abrasion machine fitted with a counter may be1This test method is under the jurisdiction of ASTM Committee D04 on
14、Roadand Paving Materials and is the direct responsibility of Subcommittee D04.51 onAggregate Tests.Current edition approved June 1,2010.Published June 2010.Originallyapproved in 2003.Last previous edition approved in 2008 as D6928 081.DOI:10.1520/D6928-10.2For referenced ASTM standards,visit the AST
15、M 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
16、FIG.1 Micro-Deval Abrasion Machine and Container(dimensions in mm)D6928 102 used if the test is conducted on the basis of number of revolutions(Section9.3.2).6.2 Containers,stainless steel Micro-Deval abrasion jarshaving an apporiximate 5-L capacity,a locking cover andgasket capable of sealing the jar and making it water-tight.External diameter of the abrasion jar shall be 194-mm to202-mm and the internal height shall be 170-mm to 177-mm.The inside and outside surfaces of the jars shall be smoot
