ASTM_D_75-19.pdf

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations isued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.Designation:D75/D75M-19American Association StateHighway and TransportationOfficials StandardINTERNATIONALAASHTO No.:T2Standard Practice forSampling Aggregates1This standard is issued under the fixed designation D75/D75M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon(8)indicates an editorial change since the last revision or reapproval.1.Scope*1.5 This international standard was developed in accor-1.1 This practice covers sampling of coarse and fine aggre-dance with internationally recognized principles on standard-gates for the following purposes:ization established in the Decision on Principles for the1.1.1 Preliminary investigation of the potential source ofDevelopment of International Standards,Guides and Recom-supply,mendations issued by the World Trade Organization Technical1.1.2 Control of the product at the source of supply,Barriers to Trade(TBT)Committee.1.1.3 Control of the operations at the site of use,and2.Referenced Documents1.1.4 Acceptance or rejection of the materials.2.1 ASTM Standards:2NoTE 1-Sampling plans and acceptance and control tests vary with theC702/C702M Practice for Reducing Samples of Aggregatetype of construction in which the material is used.to Testing Size1.2 The text of this standard references notes and footnotesD8 Terminology Relating to Materials for Roads and Pave-which provide explanatory material.These notes and footnotesments(excluding those in tables and figures)shall not be consideredD2234/D2234M Practice for Collection of a Gross Sampleas requirements of the standard.of Coal1.3 The values stated in either SI units or inch-pound unitsD3665 Practice for Random Sampling of Construction Ma-are to be regarded separately as standard.The values stated interialseach system may not be exact equivalents;therefore,eachD3666 Specification for Minimum Requirements for Agen-system shall be used independently of the other.Combiningcies Testing and Inspecting Road and Paving Materialsvalues from the two systems may result in nonconformanceE105 Practice for Probability Sampling of Materialswith the standard.E122 Practice for Calculating Sample Size to Estimate,WithSpecified Precision,the Average for a Characteristic of aNoTE 2-The quality of the results produced by this standard areLot or Processdependent on the competence of the personnel performing the procedureand the capability,calibration,and maintenance of the equipment used.E141 Practice for Acceptance of Evidence Based on theAgencies that meet the criteria of Specification D3666 are generallyResults of Probability Samplingconsidered capable of competent and objective testing,sampling,inspection,etc.Users of this standard are cautioned that compliance with3.TerminologySpecification D3666 alone does not completely ensure reliable results.Reliable results depend on many factors;following the suggestions of3.1 Definitions-For definitions of terms used in thisSpecification D3666 or some similar acceptable guideline provides apractice,refer to Terminology D8.means of evaluating and controlling some of those factors.1.4 This standard does not purport to address all of the4.Significance and Usesafety concerns,if any,associated with its use.It is the4.1 Sampling is equally as important as the testing,and theresponsibility of the user of this standard to establish appro-sampler shall use every precaution to obtain samples that willpriate safety,health,and environmental practices and deter-show the nature and condition of the materials which theymine the applicability of regulatory limitations prior to use.represent.4.2 Samples for preliminary investigation tests are obtainedby the party responsible for development of the potential This practice is under the jurisdiction of ASTM Committee D04 on Road andPaving Materials and is the direct responsibility of Subcommittee D04.30 onMethods of Sampling.2 For referenced ASTM standards,visit the ASTM website,www.astm.org,orCurrent edition approved Nov.1,2019.Published November 2019.Originallycontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMapproved in 1920.Last previous edition approved in 2014 as D75/D75M-14.DOI:Standards volume information,refer to the standards Document Summary page on10.1520/D0075_D0075M-19.the ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM Intemational,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesD75/D75M-19source(Note 3).Samples of materials for control of theveyor belt while the sample increments are being obtained.production at the source or control of the work at the site of useInsert two templates,the shape of which conforms to the shapeare obtained by the manufacturer,contractor,or other partiesof the belt in the aggregate stream on the belt,and space themresponsible for accomplishing the work.Samples for tests to besuch that the material contained between them will yield anused in acceptance or rejection decisions by the purchaser areincrement of the required weight(see Fig.1).Carefully scoopobtained by the purchaser or his authorized representative.all material between the templates into a suitable container andcollect the fines on the belt with a brush and dust pan and addNoTE 3-The preliminary investigation and sampling of potentialaggregate sources and types occupies a very important place in determin-to the container.ing the availability and suitability of the largest single constituent enteringNoTE 5-Automatic belt samplers may be used as long as they areinto the construction.It influences the type of construction from theproperly maintained,and regular inspection ensures all material is beingstandpoint of economics and governs the necessary material control toremoved from the belt(see Fig.2).ensure durability of the resulting structure,from the aggregate standpoint.This investigation should be done only by a responsible,trained,and5.3.3 Sampling from Stockpiles-Avoid sampling coarseexperienced person.For more comprehensive guidance,see the appen-aggregate or mixed coarse and fine aggregate from stockpilesdixes.whenever possible,particularly when the sampling is done forthe purpose of determining aggregate properties that may be5.Securing Samplesdependent upon the grading of the sample.If circumstances5.1 General-Where practicable,samples to be tested formake it necessary to obtain samples from a stockpile of coarsequality shall be obtained from the finished product.Samplesaggregate or a stockpile of combined coarse and fine aggregate,from the finished product to be tested for abrasion loss shall notdesign a sampling plan for the specific case under consider-be subject to further crushing or manual reduction in particleation to ensure that segregation does not introduce a bias in thesize in preparation for the abrasion test unless the size of theresults.This approach will allow the sampling agency to use afinished product is such that it requires further reduction forsampling plan that will give a confidence in results obtainedtesting purposes.therefrom that is agreed upon by all parties concerned to be5.2 Inspection-The material to be sampled shall be visuallyacceptable for the particular situation.The sampling plan shalldefine the number of samples necessary to represent lots andinspected to determine discernible variations.If any discerniblevariations are noted,corrective action shall be taken to estab-sublots of specific sizes.The sampling plan shall also definelish homogeneity in the material prior to sampling.If it isany specialized site-specific sampling techniques or proceduresthat are required to ensure unbiased samples for existingnecessary to indicate the degree of variability existing withinconditions.The owner and supplier shall agree upon the use ofthe main pile,separate samples shall be drawn from separateareas of the pile.The seller shall provide suitable equipmentany specialized site-specific techniques or procedures.Whensite-specific techniques or procedures are developed for sam-needed for proper inspection and sampling.pling a stockpile,those procedures shall supersede the proce-5.3 Procedure:dures given in 5.3.3.1.(Note 6).General principles for sam-5.3.1 Sampling from a Flowing Aggregate Stream(Bins orpling from stockpiles are applicable to sampling from trucks,Belt Discharge)-Select units to be sampled by a randomrail cars,barges,or other transportation units.method,such as Practice D3665,from the production.ObtainNoTE 6-Specific site sampling plans may include the number ofat least three approximately equal increments,selected atsampling increments(loader buckets)required to construct the samplingrandom from the unit being sampled,and combine to form apad.field sample whose mass equals or exceeds the minimum5.3.3.1 Sampling from Stockpiles with Power Equipmentrecommended in 5.4.2.Take each increment from the entire(preferred)-In sampling material from stockpiles it is verycross section of the material as it is being discharged.It isdifficult to ensure unbiased samples due to the segregationusually necessary to have a special device constructed for useat each particular plant.This device consists of a pan ofsufficient size to intercept the entire cross section of thedischarge stream and hold the required quantity of materialwithout overflowing.A set of rails may be necessary to supportthe pan as it is passed under the discharge stream.Insofar as ispossible,keep bins continuously full or nearly full to reducesegregation.NoTE 4-Sampling the initial discharge or the final few tons from a binor conveyor belt increases the chances of obtaining segregated materialand should be avoided.5.3.2 Sampling from the Conveyor Belt-Select units to besampled by a random method,such as Practice D3665,fromthe production.Obtain at least three approximately equalincrements,selected at random,from the unit being sampledand combine to form a field sample whose mass equals orexceeds the minimum recommended in 5.4.2.Stop the con-FIG.1 Belt Sampling Template24D75/D75M-19the entire flat area,but avoid sampling within 0.3 m I ftof thesample pad edge.Divide the sample pad into four quadrantsand sample equal amounts of materials evenly across eachquadrant.Fully insert the shovel as near vertical as possiblethen gently roll the shovel back and lift slowly to avoid coarsematerial rolling off the sides of the shovel(Note 7).Obtainadditional shovelfuls from different quadrants of the samplingpad,and in areas that avoid previousshovel holes.NorE 7-Square-tip shovels with the outer edges rolled up approxi-mately 50 mm 2 in.on each side work well in preventing material fromrolling from the side.Spade-tip shovels are not recommended.5.3.3.2 Sampling from Stockpiles Without Power Equip-ment:FIG.2 Automatic Belt SamplerNore 8-Sampling coarse aggregate and coarse and fine mixedaggregate stockpiles without the aid of power equipment is not advised.(1)Where power equipment is not available,samples fromwhich often occurs when material is stockpiled.with coarserstockpiles shall be made up of at least three increments takenparticles rolling to the outside base of the pile.For coarse orfrom the top third,at the mid-point,and bottom third of themixed coarse and fine aggregate,every effort shall be made toelevation of the stockpile.enlist the services of power equipment to develop a separate(2)Shove a board vertically into the pile just above thesmall sampling pile.sampling point to prevent coarser material from rolling down(/)When obtaining a sample from a stockpile for accep-and further segregating the material and biasing the sample.tance testing,a loader shall enter the stockpile nearest the areaThe board shall be of ample size to prevent material fromrepresenting material that is currently being shipped or loadedcascading down into the sampling area.into a production facility,with the bucket approximately(3)With the board in place,scrape off the outermost150 mm 6 in.above ground level,never allowing the frontsurface of the pile with the shovel.then insert the shoveltires of the loader to ramp up on the pile.Without backing up.perpendicular to the angle of the pile,into the freshly exposedthe loader shall lift the full bucket of material then tilt thematerial to obtain the sample.Repeat this process across thebucket down to gently roll the material out of the bucket backface of the stockpile until the recommended minimum fieldonto the pile,thus re-blending any segregated material on thesample size in 5.4.2 is obtained but no less than the threeoutside surface of the pile.If prior visual inspection notedincrements described in 5.3.3.2(1).discernible variation,or if the loader is not of sufficient size tocause a cascading effect down the face of the pile during this5.3.3.3 Sampling Fine Aggregate from Stockpiles(Alterna-tive Method for Fine Aggregate Only)-When sampling fineremixing process,several buckets of material shall either beaggregate from a stockpile,the outer layer,which easilyremixed or removed and discarded to prevent use of potentiallybecomes segregated by wind and rain during stockpile storage.injurious material.shall be removed and the sample taken from the material(2)After re-blending.the loader shall re-enter thestockpile,as before,and obtain a full loader bucket of thebeneath.re-blended material,tilt back,and lift the bucket only high(/Sampling tubes approximately 30 mm 1.25 in.mini-mum by 2 m 6 ftin length shall be inserted into the shippingenough to back up slightly.face of the stockpile horizontally at random locations.(3)At the base of the main stockpile with the bucket onlyhigh enough to permit free-flow of the material from theNorE 9-A sampling tube can be constructed of aluminum.PVC.orbucket,the loader operator shall tilt the bucket forward toother sturdy material.The tip being inserted into the pile can be cut at agently roll the material out of the bucket,forming a small45 angle to ease insertion.sampling pile.If the loader bucket is not of sufficient size to(2)Sample shall be taken at a minimum height of 3 ft fromcreate a sample pad of representative size.multiple bucketsthe surrounding grade.shall be used,dumped on top of each other and back-dragged(3)A minimum of five tube insertions randomly spacedacross the face of the stockpile shall form a single field sampleto form a single sample pad.(4)At this point the loader operator shall raise the bucket,(see Fig.4).Ensure that the minimum field sample sizedrive forward far enough to reach across the small pile with therecommended in 5.4.2 is obtained.loader bucket without allowing the loader tires to ramp up on5.3.4 Sampling from Transportation Units-Avoid samplingthe sampling pile,lower the bucket to about half the height ofcoarse aggregate or mixed coarse and fine aggregate fromthe small pile,and backup,therefore creating a flat surface fortransportation units whenever possible,particularly when thesampling(see Fig.3).The loader shall only back-drag thesampling is done for the purpose of determining aggregatesmall pile once.This flat surface provides a stable and safe areaproperties that may be dependent upon the grading of theto obtain a representative sample.sample.If circumstances make it necessary to obtain samples(5)Place the sample bucket(s)near the center of the flat,from a transportation unit,design a sampling plan for theoval-shaped sampling pad.The sample shall be obtained acrossspecific case under consideration to ensure that segregation4D75/D75M-19Step 1.Loader enters stockpile with bucket approximatelyStep 3.Loader reaches across the small pile,lowers150mm 6 in.above ground levelbucket,and back-drags small pile to form the samplingpadStep 2.Loader gently rolls the material out of the bucketStep 4.Sampling padto fom a small pileStep 5.Draw sample portions from each quadrantFIG.3 Five-Step Photographic Sequence of Constructing Sampling Pad from Stockpile of AggregateFIG.4 Sampling Fine Aggregate from Stockpile Using Sampling Tubedoes not introduce a bias in the results.This approach willa confidence in results obtained therefrom that is agreed uponallow the sampling agency to use a sampling plan that will giveby all parties concerned to be acceptable for the particular4D75/D75M-19situation.The sampling plan shall define the number of5.3.5.3 A metal template placed over the area will aid insamples necessary to represent lots and sublots of specificsecuring approximately equal increment weights.Place thesizes.General principles for sampling from stockpiles aretemplate on top of the material to be sampled.Sample materialapplicable to sampling from trucks,rail cars,barges,or otherfrom the center of the template.As material is extracted fromtransportation units.the center of the template,the template is continuously loweredNorE 10-Sampling from transportation units should be avoided if atto prevent the material outside of the template from falling intoall possible.In sampling material from transportation units it is verythe sample hole.The template shall be composed of metal ordifficult to ensure unbiased samples,due to the segregation which oftenother sturdy material,no less than 0.3 m 12 in.in diameteroccurs when material is transported,with coarser particles rolling to theand 0.25 m 9 in.in height,providing a sampling area not lessoutside and finer particles settling.than 0.07 m 110 in.(see Fig.5).5.3.4.1 In sampling coarse aggregates from railroad cars or5.4 Number and Masses of Field Samples:barges,effort shall be made to enlist the services of power5.4.1 The number of field samples(obtained by one of theequipment capable of exposing the material at various levelsmethods described in 5.3)required depends on the criticalityand random locations.of,and variation in,the properties to be measured.Designate5.3.4.2 Where power equipment is not available,a commoneach unit from which a field sample is to be obtained prior toprocedure requires excavation of three or more trenches usingsampling.The number of field samples from the productiona shovel across the unit at points that will,from visualshall be sufficient to give the desired confidence in test results.appearance,give a reasonable estimate of the characteristics ofthe load.The trench bottom shall be approximately level,atNorE 11-Guidance for determining the number of samples required toleast 0.3 m I ftin width and in depth below the surface.obtain the desired level of confidence in test results may be found inPractices D2234/D2234M,E105,E122,and E141.5.3.4.3 A minimum of three increments from approximatelyequally spaced points along each trench shall be taken by5.4.2 The field sample masses cited are tentative.Thepushing a shovel downward into the material.masses must be predicated on the type and number of tests to5.3.4.4 Coarse aggregate in trucks shall be sampled inwhich the material is to be subjected and sufficient materialessentially the same manner as for rail cars or barges,exceptobtained to provide for the proper execution of these tests.for adjusting the number of increments according to the size ofStandard acceptance and control tests are covered by ASTMthe truck.standards and specify the portion of the field sample required5.3.4.5 For fine aggregate in transportation units,samplingfor each specific test.Generally speaking,the amounts speci-tubes as described in 5.3.3.3,except inserted vertically,may befied in Table I will provide adequate material for routineused to extract an appropriate number of increments from thegrading and quality analysis.Extract test portions from thetrenches to form the field sample.field sample according to Practice C702/C702M or as required5.3.5 Sampling from Roadway(Bases and Subbases):by other applicable test methods.5.3.5.1 Sample units selected by a random method,such as6.Shipping SamplesPractice D3665.from the construction.5.3.5.2 Obtain at least three approximately equal6.1 Transport aggregates in bags or other containers soincrements,selected at random from the unit being sampled.constructed as to preclude loss or contamination of any part ofafter the material has been placed and prior to compaction,andthe sample,or damage to the contents from mishandling duringcombine to form a field sample whose mass equals or exceedsshipment.the minimum recommended in 5.4.2.Take all increments from6.2 Shipping containers for aggregate samples shall havethe roadway for the full depth of the material,taking care tosuitable individual identification attached and enclosed so thatexclude any underlying material.Clearly mark the specificfield reporting,laboratory logging.and test reporting may beareas from which each sample increment is to be removed.facilitated.FIG.5 Proper Use of Metal Template For Sampling Mixed Coarse and Fine Aggregate From Roadway Grade