1、Designation: C873/C873M 10aStandard Test Method forCompressive Strength of Concrete Cylinders Cast in Placein Cylindrical Molds1This standard is issued under the fixed designation C873/C873M; the number immediately following the designation indicates the yearof original adoption or, in the case of r
2、evision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () 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. Scope*1.1 This test metho
3、d covers the determination of strength ofcylindrical concrete specimens that have been molded in placeusing special molds attached to formwork. This test method islimited to use in slabs where the depth of concrete is from 125to 300 mm 5 to 12 in.1.2 UnitsThe values stated in either SI units or inch
4、-pound units are to be regarded separately as standard. Thevalues stated in each system may not be exact equivalents;therefore, each system shall be used independently of the other.Combining values from the two systems may result in non-conformance with the standard.1.3 This standard does not purpor
5、t to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to consult andestablish appropriate safety and health practices and deter-mine the applicability of regulatory limitations prior to use.(WarningFresh hydraulic cementitious m
6、ixtures are causticand may cause chemical burns to skin and tissue uponprolonged exposure.2)2. Referenced Documents2.1 ASTM Standards:3C39/C39M Test Method for Compressive Strength of Cy-lindrical Concrete SpecimensC42/C42M Test Method for Obtaining and Testing DrilledCores and Sawed Beams of Concre
7、teC470/C470M Specification for Molds for Forming Con-crete Test Cylinders VerticallyC617 Practice for Capping Cylindrical Concrete SpecimensC670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsC1231/C1231M Practice for Use of Unbonded Caps inDeterminati
8、on of Compressive Strength of Hardened Con-crete Cylinders3. Summary of Test Method3.1 A concrete cylinder mold assembly consisting of a moldand a tubular support member is fastened within the concreteformwork prior to placement of the concrete as shown in Fig.1. The elevation of the mold upper edge
9、 is adjusted tocorrespond to the level of the finished slab surface. The moldsupport prevents direct contact of the slab concrete with theoutside of the mold and permits easy removal of the mold fromthe slab. The mold is filled at the time its location is reached inthe normal course of concrete plac
10、ement. The specimen in the“cured-in-place” condition is removed from its in-place loca-tion immediately prior to de-molding, capping, and testing.The reported compressive strength is corrected on the basis ofspecimen length-diameter ratio using correction factors pro-vided in the section on calculat
11、ion of Test Method C42/C42M.4. Significance and Use4.1 Cast-in-place cylinder strength relates to the strength ofconcrete in the structure due to the similarity of curingconditions because the cylinder is cured within the slab.However, due to differences in moisture condition, degree ofconsolidation
12、, specimen size, and length-diameter ratio, thereis not a unique relationship between the strength of cast-in-place cylinders and cores of the same age. When cores can bedrilled undamaged and tested in the same moisture condition asthe cast-in-place cylinders, the strength of the cylinders can be1Th
13、is test method is under the jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.61 on Testing for Strength.Current edition approved Dec. 15, 2010. Published January 2011. Originallyapproved in 1977. Last previous edition approved
14、in 2010 as C873/C873M10.DOI: 10.1520/C0873_C0873M-10a.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
15、 Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.expected to
16、be on average 10 % higher than the cores at agesup to 91 days for specimens of the same size and length-diameter ratio.44.2 Strength of cast-in-place cylinders may be used forvarious purposes, such as estimating the load-bearing capacityof slabs, determining the time of form and shore removal, andde
17、termining the effectiveness of curing and protection.5. Apparatus5.1 Cast-in-place molds shall have a diameter at least threetimes the nominal maximum aggregate size. The length-diameter ratio (L/D) of the specimen after capping shall not beless than 1.0 (see Note 1). Molds (inner member) shall beco
18、nstructed in one piece in the form of right circular cylindersat least 100 mm 4 in. in inside diameter with the average4Bloem, D. L., “Concrete Strength in Structures,” Journal of the AmericanConcrete Institute, JACIA, March 1968, or ACI Proceedings, PACIA, Vol. 65, No.3, pp. 169248.FIG. 1 Schematic
19、 of Cast-in-Place Cylinder Mold AssemblyC873/C873M 10a2diameter not differing from the nominal diameter by more than1 % and no individual diameter differing from any otherdiameter by more than 2 %. The plane of the rim of the moldand the bottom shall be perpendicular to the axis of the moldwithin 0.
20、5 (approximately equivalent to 1 mm in 300 mm 18in. in 12 in.).NOTE 1The length-diameter ratio should preferably be between 1.5and 2.0.5.2 Molds shall be watertight and meet the criteria of thesection on water leakage of Specification C470/C470M. Moldsand auxiliary apparatus shall be made of nonabso
21、rbent materialthat does not react with concrete containing portland or otherhydraulic cements. They shall be sufficiently strong and toughto permit use under normal construction conditions withouttearing, crushing, or otherwise deforming permanently whenfilled with fresh concrete. They shall resist
22、permanent defor-mation to the extent that they produce hardened concretecylinders such that two diameters measured at right angles toeach other in any horizontal plane do not differ by more than2.0 mm 116 in.5.3 The exterior top of the mold shall have outwardlyextending centering knobs and an annula
23、r flange to rest on topof the support member (5.4) and to seal the annular ring spacebetween the mold and that support member. Means for twistingand vertical withdrawal of molds from the support membershall be provided in the annular flange (see Fig. 1).5.4 Support members shall be right circular cy
24、linders andshall be rigid tubes of diameter required to accommodatemolds stipulated in 5.1 and to concentrically contact andsupport the annular flange of the mold. Support members shallbe provided with a means for height adjustment and shall befitted with exterior means to permit nailing or other fi
25、rmattachment to slab forms in a manner preventing entry ofconcrete or mortar into the annular ring space between thesupport member and the mold.6. Installation of Apparatus6.1 After completion of reinforcing steel placement andother formwork preparation, fasten the support member to slabforms using
26、nails or screws. Adjust the support member so thatthe top of the mold is aligned with the elevation of screedguides used in striking off the concrete.NOTE 2The location of mold assemblies should be noted on projectdrawings for easy location after concrete placement and for identification.6.2 Place t
27、he mold in the support member so that the flangeof the mold is uniformly supported by the sleeve to preventconcrete or mortar from penetrating into the space between themold and support member.NOTE 3Insertion of compressible material between the support mem-ber and the mold is permitted to prevent m
28、ortar seepage into the annularspace.7. Procedure7.1 Inspect the molds to ensure they are clean and free ofany debris or foreign matter. Fill the molds when the concreteplacement progresses to the vicinity of mold location.7.2 ConsolidationConsolidate concrete in the mold tosimulate the conditions of
29、 placement. In normal field construc-tion practice, if the surrounding concrete is consolidated byinternal vibration, use the vibrator externally, briefly touchingthe exterior of the mold support member. Internal vibration ofconcrete in the mold is prohibited except under specialcircumstances that s
30、hall be explained in the report of testresults. Subject the specimen surface to the same finishing asthe surrounding concrete.7.3 Curing of SpecimensSubject the specimens to thesame curing and treatment as provided to the surroundingconcrete. Record maximum and minimum slab surface tem-peratures dur
31、ing the curing period for inclusion in the report.Specimen molds shall remain fully seated in place until time ofremoval for transportation to the testing location.7.4 Mold RemovalRemove molds from support members,exercising care so as not to physically damage specimens.From the time of removal from
32、 the structure until time of test,maintain test specimens at a temperature within 65C610F of the slab surface temperature at the time of removal.Transport specimens to the laboratory within 4 h after removal.During transportation protect the specimens with suitablematerial to prevent damage from jar
33、ring, to insulate them fromextreme ambient temperatures, and to prevent moisture loss.7.5 Testing of SpecimensRemove specimens from molds.Determine the average diameter of each specimen to thenearest 0.2 mm 0.01 in. by averaging two diameters mea-sured at right angles to each other at about the midh
34、eight of thespecimen. Cap specimens in accordance with Practice C617and measure the length of the capped specimens to the nearest2 mm 0.1 in. Alternatively, measure the length of thespecimens to the nearest 2 mm 0.1 in. and use unbonded capsin accordance with Practice C1231/C1231M. Test the speci-me
35、ns in accordance with Test Method C39/C39M. Test thespecimens for compressive strength in the “as-received” mois-ture condition unless required otherwise by project specifica-tions.8. Calculation8.1 Calculate the compressive strength of each specimenusing the computed cross-sectional area based on t
36、he averagediameter of the specimen. If the length-diameter ratio of thespecimen is 1.75 or less, correct the calculated strength bymultiplying by the applicable strength correction factor givenin Test Method C42/C42M.9. Report9.1 Report the following information:9.1.1 Identification of structure in
37、which specimens werecast, identification of specimen, and location of the mold in thestructure,9.1.2 Diameter and length, mm in.,9.1.3 Maximum load, N lbf,9.1.4 The L/D strength correction factor used,9.1.5 Compressive strength calculated to the nearest 10 psi0.1 MPa after multiplying by the applica
38、ble L/D strengthcorrection factor, if required,9.1.6 Type of fracture (see Test Method C39/C39M),9.1.7 Defects in specimen, or caps, if observed,9.1.8 Age of specimen,9.1.9 Curing methods used,C873/C873M 10a39.1.10 Initial concrete temperature,9.1.11 Maximum and minimum temperature informationobtain
39、ed at job site to define curing conditions of specimens inplace,9.1.12 Detailed descriptions of any internal vibration orother internal manipulations of the fresh concrete in the mold(7.2), and9.1.13 Other information pertaining to job conditions thatcould affect the results.10. Precision and Bias10
40、.1 PrecisionThe single-operator coefficient of variationhas been found to be 3.5 %5for a range of compressivestrength between 10 and 41 MPa 1500 and 6000 psi.6Therefore, results of two properly conducted tests by the sameoperator on the same sample of concrete should not differ fromeach other by mor
41、e than 10.0 %5of their average. Largerdifferences may be due to improperly prepared specimens oractual strength differences because of different batches ofconcrete or different curing conditions.10.2 BiasThe bias of this test method cannot be deter-mined because the strength of a cast-in-place cylin
42、dricalspecimen can only be obtained by using this test method.11. Keywords11.1 compressive strength; concrete; cylinder molds; in-place strengthSUMMARY OF CHANGESCommittee C09 has identified the location of selected changes to this test method since the last issue,C873/C873M10, that may impact the u
43、se of this test method. (Approved December 15, 2010.)(1) Revised 7.2 to eliminate non-mandatory language. (2) Revised the temperature range in SI units in 7.4 to a morerational value and clarified the needs for protection duringtransportation.Committee C09 has identified the location of selected cha
44、nges to this test method since the last issue,C873/C873M04e1, that may impact the use of this test method. (Approved June 15, 2010.)(1) The order of the inch-pound and SI units was reversed.(2) Minor revisions were made to 3.1 to improve clarity.(3) Minor revisions were made to 4.1 to clarify the in
45、tent of thesecond sentence.(4) A new Note 1 was added to remove non-mandatory textfrom the body of the standard and subsequent notes wererenumbered.(5) A minor revision was made to 5.2 to clarify that the intentis to prevent permanent distortion of the molds.(6) Additional text was added to 5.3 to c
46、larify how the moldsare used.(7)In5.4, the reference to attaching molds to reinforcing steelwas removed because this is not done in practice.(8) Minor changes were made to 6.1 and the last sentence wasmoved to a new Note 2.(9) 7.5 was revised to permit the use of unbonded caps.ASTM International tak
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48、sponsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addres
49、sed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by
