1、Designation:C7013American Association StateHighway and Transportation Officials StandardAASHTO No.:T142Standard Test Method forSurface Moisture in Fine Aggregate1This standard is issued under the fixed designation C70;the number immediately following the designation indicates the year of originalado
2、ption or,in the case of revision,the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1.Scope1.1
3、 This test method covers field determination of theamount of surface moisture in fine aggregate by displacementin water.1.2 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-priat
4、e safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.3 The values stated in SI units are to be regarded as thestandard.No other units of measurement are included in thisstandard.2.Referenced Documents2.1 ASTM Standards:2C128 Test Method for Density,
5、Relative Density(SpecificGravity),and Absorption of Fine AggregateC566 Test Method for Total Evaporable Moisture Content ofAggregate by DryingC670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction Materials3.Significance and Use3.1 This test method is not widely u
6、sed.However,it is aconvenient procedure for field or plant determination ofmoisture content of fine aggregate if specific gravity values areknown and if drying facilities are not available.It can be usedto adjust the aggregate mass for moisture content and todetermine surface moisture contribution t
7、o mixing water inportland cement concrete.3.2 The accuracy of the test method depends upon accurateinformation on the bulk specific gravity of the material in asaturated surface-dry condition.4.Apparatus4.1 Balance,having a capacity of 2 kg or more and sensitiveto 0.5 g or less.4.2 FlaskA suitable c
8、ontainer or flask,preferably of glassor noncorrosive metal.The container may be a pycnometer,avolumetric flask,a graduated volumetric flask,or other suitablemeasuring device.The volume of the container shall be fromtwo to three times the loose volume of the sample.Thecontainer shall be so designed t
9、hat it can be filled to the mark,or the volume of its contents read,within 0.5 mL or less.5.Sample5.1 Select a representative sample of the fine aggregate to betested for surface moisture content.It shall weigh not less than200 g.Larger samples will yield more accurate results.6.Procedure6.1 The sur
10、face water content may be determined either bymass or volume.In each case the test shall be made at atemperature range of 18 to 29C.6.2 Determination by MassDetermine the mass of thecontainer,in grams,filled to the mark with only water.Beforeplacing the sample into the container,adjust the level of
11、thewater so that it will be sufficient to cover the sample withoutgoing over the original mark.Introduce the weighed sample offine aggregate into the container and remove the entrapped air.Fill the container to the original mark,and determine the massin grams.Calculate the amount of water displaced
12、by thesample,as follows:Md5 Mc1Ms2 M(1)where:Md=mass of water displaced by the sample,g,Mc=mass of container filled to the mark with water,g,Ms=mass of sample,g,andM=mass of container and sample,filled to the mark withwater,g.1This test method is under the jurisdiction of ASTM Committee C09 onConcre
13、te and Concrete Aggregatesand is the direct responsibility of SubcommitteeC09.20 on Normal Weight Aggregates.Current edition approved Feb.1,2013.Published February 2013.Originallyapproved in 1970.Last previous edition approved in 2006 as C70 06.DOI:10.1520/C0070-13.2For referenced ASTM standards,vis
14、it 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.Unite
15、d States1 6.3 Determination by VolumeMeasure a volume of water,in millilitres,sufficient to cover the sample and place in thecontainer.Introduce the weighed sample of fine aggregate intothe container and remove the entrapped air.Determine thecombined volume of the sample and the water by direct read
16、ingwhen a graduated flask is used.When a pycnometer orvolumetric flask of known volume is used,fill the container tothe known volume mark with an additional measured volumeof water.The flask or pycnometer volume is then equal to thecombined volume of sample and water.Calculate the amountof water displaced by the sample,as follows:Vs5 V22 V1(2)where:Vs=volume of water displaced by the sample,mL,V2=combined volume of sample and water,mL,andV1=total volume of water in the flask or pycnometerrequire