1、Designation:C1542/C1542M16aStandard Test Method forMeasuring Length of Concrete Cores1This standard is issued under the fixed designation C1542/C1542M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.A number
2、 in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method is used to determine the length of acore drilled from concrete.1.2 The values stated in either SI units or inch-pound unitsare
3、to be regarded separately as standard.Within the text,theinch-pound units are shown in brackets.The values stated ineach system are not exact equivalents;therefore,each systemshall be used independently of the other.1.3 This standard does not purport to address all of thesafety concerns,if any,assoc
4、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:2C42/C42M Test Method for Obtaining and Testing DrilledCores
5、and Sawed Beams of ConcreteC125 Terminology Relating to Concrete and Concrete Ag-gregatesC174/C174M Test Method for Measuring Thickness of Con-crete Elements Using Drilled Concrete CoresC670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsC1604/C1604M T
6、est Method for Obtaining and TestingDrilled Cores of Shotcrete3.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this test method,referto Terminology C125.4.Significance and Use4.1 This test method provides two procedures for determin-ing the length of a core obtained in accordance
7、with either TestMethod C42/C42M or Test Method C1604/C1604M.Thislength is used in conjunction with condition surveys,densityand voids analysis,and other applications.4.2 This procedure does not intend to include in the lengthmeasurement adhered particles not part of the concrete mix-ture.4.3 Test Me
8、thod C174/C174M also determines the length ofconcrete cores using a different measuring apparatus andprocedure.NOTE1Test Method C174/C174M uses an apparatus that establishestwo parallel planes a known distance apart.The length of the core isdetermined by calculation using the known distance between
9、the twoparallel planes and the measured distance from the upper plane to the topof the core.5.Apparatus5.1 Jaw Caliper,minimum depth of jaw 65 mm 2.5 in.Measuring range 0 to 300 mm 0 to 12 in.Accuracy to 0.02mm 0.001 in.or better.5.1.1 Offset points as part of caliper accessory kit to permitlength m
10、easurements at points not on the core perimeter.5.2 Ruler,300 to 380 mm 12 to 15 in.divided into 1 mm116or 0.1 in.graduations.6.Test Specimens6.1 Cores shall be obtained in accordance with Test MethodC42/C42M or Test Method C1604/C1604M.6.2 Cores shall be intact and be free of any coatings.7.Procedu
11、re7.1 Jaw Caliper Procedure:7.1.1 Attach offset points to caliper jaws and initialize zeroreading.7.1.2 Hold the specimen and place the open jaws of thecaliper midpoint between the center and edge of the specimen.Measure and record the value to the nearest 0.25 mm 0.01 in.Rotate the specimen 90,180,
12、and 270 and repeat procedure.Obtain one measurement along the axis of the specimen andrecord.7.1.3 Re-zero the calipers.If the zero reading has changedby more than 0.25 mm 0.01 in.take a new set of measure-ments as described in 7.1.2.7.2 Ruler Procedure:1This test method is under the jurisdiction of
13、 ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.61 on Testing for Strength.Current edition approved June 1,2016.Published June 2016.Originallyapproved in 2002.Last previous edition approved in 2016 as C1542/C1542M 16.DOI:10.1520/C1542_C1542M
14、-16A.2For referenced ASTM standards,visit 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.*A Summary of Changes section appears at the end of this stan
15、dardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 7.2.1 Position core with finished or formed face placeddown against flat and level surface.Place ruler on flat surfaceagainst side of core and measure length to nearest 1 mm 116or0.05 in
16、.(Note 2)and record.Rotate core and repeat measure-ments at approximately 90,180,and 270.NOTE2If using a ruler with 0.1 in.divisions,estimate to the nearesthalf division.7.2.2 If a core drilled from a pavement or structure placedon an aggregate base course includes particles of the basecourse bonded to the bottom surface of the concrete,thebonded material shall not be included in any measurements.Use the ruler procedure when measuring cores with adheringmaterial.Measure from the end of the core
