1、Designation:C172/C172M14aStandard Practice forSampling Freshly Mixed Concrete1This standard is issued under the fixed designation C172/C172M;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 parent
2、heses indicates the year of last reapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This practice covers procedures for obtaining represen-tative samples of fresh concrete as delivered to the project siteon which tests are to be performe
3、d to determine compliancewith quality requirements of the specifications under which theconcrete is furnished(Note 1).The practice includes samplingfrom stationary,paving and truck mixers,and from agitatingand nonagitating equipment used to transport central-mixedconcrete and from continuous mixing
4、equipment as describedin Specification C685/C685M.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
5、two systems may result in non-conformancewith the standard.NOTE1Composite samples are required by this practice,unlessspecifically excepted by procedures governing the tests to be performedsuch as tests to determine uniformity of consistency and mixer efficiency.Procedures used to select the specifi
6、c test batches are not described in thispractice,but it is recommended that random sampling be used todetermine overall specification compliance.1.3 This practice also covers the procedures to be used forpreparing a sample of concrete for further testing where it isdesirable or necessary to remove t
7、he aggregate larger than adesignated size.This removal of larger aggregate particles ispreferably accomplished by wet-sieving.1.4 The text of this standard references notes and footnoteswhich provide explanatory material and shall not be consideredas requirements of the practice.1.5 This standard do
8、es 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-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.(WarningFreshhydraulic cementitious mi
9、xtures are caustic and may causechemical burns to skin and tissue upon prolonged exposure.2)2.Referenced Documents2.1 ASTM Standards:3E11 Specification for Woven Wire Test Sieve Cloth and TestSievesC685/C685M Specification for Concrete Made by Volumet-ric Batching and Continuous Mixing3.Significance
10、 and Use3.1 This practice is intended to provide standard require-ments and procedures for sampling freshly mixed concretefrom different containers used in the production or transporta-tion of concrete.The detailed requirements as to materials,mixtures,air content,temperature,number of specimens,slu
11、mp,interpretation of results,and precision and bias are inspecific test methods.4.Sampling4.1 The elapsed time shall not exceed 15 min.betweenobtaining the first and final portions of the composite sample.4.1.1 Transport the individual samples to the place wherefresh concrete tests are to be perform
12、ed or where test speci-mens are to be molded.They shall be combined and remixedwith a shovel the minimum amount necessary to ensureuniformity and compliance with the maximum time limitsspecified in 4.1.2.4.1.2 Start tests for slump,temperature,and air contentwithin 5 min after obtaining the final po
13、rtion of the compositesample.Complete these tests expeditiously.Start moldingspecimens for strength tests within 15 min after fabricating thecomposite sample.Expeditiously obtain and use the sampleand protect the sample from the sun,wind,and other sources ofrapid evaporation,and from contamination.1
14、This practice is under the jurisdiction of ASTM Committee C09 on Concreteand ConcreteAggregates and is the direct responsibility of Subcommittee C09.60 onTesting Fresh Concrete.Current edition approved Oct.1,2014.Published November 2014.Originallyapproved in 1942.Last previous edition approved in 20
15、14 as C17214.DOI:10.1520/C0172_C0172M-14A.2Section on Safety Precautions,Manual of Aggregate and Concrete Testing,Annual Book of ASTM Standards,Vol 04.02.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStand
16、ards volume 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 5.Procedure5.1 Size of SampleMake the samples to be used forstrength tests a minimum of 28 L 1 ft3.Smaller samples arenot prohibited for routine air content,temperature,and slumptests.The size of the samples shall be dictated by the maxi
