1、Designation: C 873 04Standard Test Method forCompressive Strength of Concrete Cylinders Cast in Placein Cylindrical Molds1This standard is issued under the fixed designation C 873; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, th
2、e year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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 method covers t
3、he 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 5 to12 in. 125 to 300 mm.1.2 The values stated in either inch-pounds or SI units shallb
4、e regarded separately as standard. SI units are shown inbrackets. The values stated may not be exact equivalents,therefore each system must be used independently of the other.Combining values of the two units may result in nonconfor-mance.1.3 This standard does not purport to address all of thesafet
5、y 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 mixtures are causticand may c
6、ause chemical burns to skin and tissue uponprolonged exposure.2)2. Referenced Documents2.1 ASTM Standards:3C 39/C 39M Test Method for Compressive Strength of Cy-lindrical Concrete SpecimensC 42/C 42M Test Method for Obtaining and Testing DrilledCores and Sawed Beams of ConcreteC 470/C 470M Specifica
7、tion for Molds for Forming Con-crete Test Cylinders VerticallyC 617 Practice for Capping Cylindrical Concrete Speci-mensC 670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction Materials3. Summary of Test Method3.1 A concrete cylinder mold assembly consisting of a
8、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 is adjusted tocorrespond to the plane of the finished slab surface. The moldsupport prevents direct contact of the slab concrete with th
9、eoutside of the mold and permits its easy removal from thehardened concrete. The mold is filled at the time its location isreached in the normal course of concrete placement. Thespecimen in the “cured-in-place” condition is removed from itsin-place location immediately prior to de-molding, capping,a
10、nd testing. The reported compressive strength is corrected onthe basis of specimen length-diameter ratio using correctionfactors provided in the section on calculation of Test MethodC 42/C 42M.4. Significance and Use4.1 Cast-in-place cylinder strength relates to the strength ofconcrete in the struct
11、ure due to the similarity of curingconditions since the cylinder is cured within the slab. However,due to differences in moisture condition, degree of consolida-tion, specimen size, and length-diameter ratio, there is not aconstant relationship between the strength of cast-in-placecylinders and core
12、s. When cores can be drilled undamaged andtested in the same moisture condition as the cast-in-placecylinders, the strength of the cylinders can be expected to be onaverage 10 % higher than the cores at ages up to 91 days forspecimens of the same size and length-diameter ratio.44.2 Strength of cast-
13、in-place cylinders may be used forvarious purposes, such as estimating the load-bearing capacity1This 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 approve
14、d June 1, 2004. Published July 2004. Originally approvedin 1977. Last previous edition approved in 1999 as C 873 99.2Section 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,
15、orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Bloem, D. L., “Concrete Strength in Structures,” Journal of the AmericanConcrete Institute, JACIA, March 1968, or ACI Proceedings,
16、 PACIA, Vol. 65, No.3, pp. 169248.1*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.of slabs, determining the time of form and shore removal, anddetermining the effectiv
17、eness 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 and should preferably be between 1.5 and 2.0.Molds (inner member) s
18、hall be constructed in one piece in theform of right circular cylinders at least 4 in. 100 mm in insidediameter with the average diameter not differing from thenominal diameter by more than 1 % and no individual diameterdiffering from any other diameter by more than 2 %. The planeof the rim of the m
19、old and the bottom shall be perpendicular tothe axis of the mold within 0.5 (approximately equivalent to18 in. in 12 in. 1 mm in 100 mm).5.2 Molds shall be watertight and meet the criteria of thesection on water leakage of Specification C 470/C 470M.Molds and auxiliary apparatus shall be made of non
20、absorbentmaterial that does not react with concrete containing portlandFIG. 1 Schematic of Cast-in-Place Cylinder Mold AssemblyC873042or other hydraulic cements. They shall be sufficiently strongand tough to permit use under normal construction conditionswithout tearing, crushing, or otherwise defor
21、ming when filledwith fresh concrete. They shall resist deformation to the extentthat they produce hardened concrete cylinders such that twodiameters measured at right angles to each other in anyhorizontal plane do not differ by more than116 in. 2.0 mm.5.3 The exterior top of the mold shall have outw
22、ardlyextending centering knobs and an annular 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 shall be provided in theannular flange (see Fig. 1).5.4 Support members shall
23、be right circular cylinders 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
24、 nailing or other firmattachment to slab forms or reinforcing steel in a mannerpreventing entry of concrete or mortar into the annular ringspace between the support member and the mold.6. Installation of Apparatus6.1 After completion of reinforcing steel placement andother formwork preparation, fast
25、en the support member to slabforms using nails or screws. Adjust the support member so thatthe tops of the molds are aligned with the elevation of otherscreeds. The location of mold assemblies should be noted onthe project plans for easy location after concrete placement,and for identification.6.2 P
26、lace the 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 1Insertion of compressible material between the support mem-ber and the mold is permitted to pre
27、vent mortar 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 Consolidation of concrete in the mold may be varied tosimulate the c
28、onditions of 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 specialcircumst
29、ances, which shall 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
30、-peratures during 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 Remove molds from support members, exercising careso as not to physically damage specimens. From the time ofremoval fr
31、om the structure until time of test, maintain testspecimens at a temperature within 610 F 66 C of the slabsurface temperature at the time of removal. Transport speci-mens to the laboratory within 4 h after removal. Duringtransportation protect the specimens with suitable material toprevent damage fr
32、om jarring, freezing temperatures or mois-ture loss, or combination thereof.7.5 Testing of SpecimensRemove specimens from molds.Determine the average diameter of each specimen to thenearest 0.01 in 0.2 mm by averaging two diameters measuredat right angles to each other at about the midheight of thes
33、pecimen. Cap specimens in accordance with Practice C 617,measure the length of the capped specimens to the nearest 0.1in. 2 mm, and test in accordance with Test Method C 39/C 39M. Test the specimens for compressive strength in the“as-received” moisture condition unless required otherwise byproject s
34、pecifications.8. Calculation8.1 Calculate the compressive strength of each specimenusing the computed cross-sectional area based on the averagediameter of the specimen. If the length-diameter ratio of thespecimen is 1.75 or less, correct the calculated strength bymultiplying by the applicable streng
35、th correction factor givenin Test Method C 42/C 42M.9. Report9.1 Report the following information:9.1.1 Identification of structure in which specimens werecast, identification of specimen, and location of the mold in thestructure,9.1.2 Diameter and length, in. mm,9.1.3 Maximum load, lbf N,9.1.4 The
36、L/D strength correction factor used,9.1.5 Compressive strength calculated to the nearest 10 psi0.1 MPa after multiplying by the applicable L/D strengthcorrection factor, if required,9.1.6 Type of fracture (see Test Method C 39/C 39M),9.1.7 Defects in specimen, or caps, if observed,9.1.8 Age of speci
37、men,9.1.9 Curing methods used,9.1.10 Initial concrete temperature,9.1.11 Maximum and minimum temperature informationobtained 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
38、 mold(7.2), and9.1.13 Other information pertaining to job conditions thatcould affect the results.C87304310. Precision and Bias10.1 PrecisionThe single-operator coefficient of variationhas been found to be 3.5 %5for a range of compressivestrength between 1500 and 6000 psi 10 and 41 MPa.6Therefore, r
39、esults of two properly conducted tests by the sameoperator on the same sample of concrete should not differ fromeach other by more than 10.0 %5of their average. Largerdifferences may be due to improperly prepared specimens oractual strength differences because of different batches ofconcrete or diff
40、erent curing conditions.10.2 BiasThe bias of this test method cannot be deter-mined because the strength of a cast-in-place cylindricalspecimen can only be obtained by using this test method.11. Keywords11.1 compressive strength; concrete; cylinder molds; in-place strengthSUMMARY OF CHANGESCommittee
41、 C09 has identified the location of selected changes to this test method since the last issue,C 873 99, that may impact the use of this test method. (Approved June 1, 2004)(1) Simplified the wording in 1.1.(2) Added a warning about chemical burns in 1.3.(3) Added a step to the procedure in 7.5 to me
42、asure thediameter and length of the test specimens.(4) Clarified the application of the L/D strength correctionfactor in 8.1.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are ex
43、pressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revi
44、sed, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you ma
45、y 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 Sta
46、tes. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).5These numbers represent, respectively, the (1s %) and (d2s %) limits asdescribed in Practice C 670.6This statement was derived from research data reported by Nicholas J. Carino,H. S. Lew, and Charles K. Volz in “Early Age Temperature Effects on ConcreteStrength Prediction by the Maturity Method,” ACI Journal, Vol 80, No. 2,MarchApril 1983.C873044
copyright@ 2008-2019 麦多课文库(www.mydoc123.com)网站版权所有
备案/许可证编号:苏ICP备17064731号-1