ASTM C825-2006(2011) Standard Specification for Precast Concrete Barriers《预制混凝土栅栏标准规格》.pdf

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1、Designation: C825 06 (Reapproved 2011)Standard Specification forPrecast Concrete Barriers1This standard is issued under the fixed designation C825; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number

2、 in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers precast concrete barriers, in-tended to be used adjacent to a roadway or as a median, toredirect vehicles unintenti

3、onally leaving the roadway.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.2. Referenced Documents2.1 ASTM Standards:2A82/A82M Specif

4、ication for Steel Wire, Plain, for ConcreteReinforcementA185/A185M Specification for Steel Welded Wire Rein-forcement, Plain, for ConcreteA416/A416M Specification for Steel Strand, UncoatedSeven-Wire for Prestressed ConcreteA421/A421M Specification for Uncoated Stress-RelievedSteel Wire for Prestres

5、sed ConcreteA496/A496M Specification for Steel Wire, Deformed, forConcrete ReinforcementA497/A497M Specification for Steel Welded Wire Rein-forcement, Deformed, for ConcreteA615/A615M Specification for Deformed and PlainCarbon-Steel Bars for Concrete ReinforcementA996/A996M Specification for Rail-St

6、eel and Axle-SteelDeformed Bars for Concrete ReinforcementC31/C31M Practice for Making and Curing Concrete TestSpecimens in the FieldC33 Specification for Concrete AggregatesC39/C39M Test Method for Compressive Strength of Cy-lindrical Concrete SpecimensC42/C42M Test Method for Obtaining and Testing

7、 DrilledCores and Sawed Beams of ConcreteC150 Specification for Portland CementC173/C173M Test Method for Air Content of FreshlyMixed Concrete by the Volumetric MethodC231 Test Method for Air Content of Freshly Mixed Con-crete by the Pressure MethodC260 Specification for Air-Entraining Admixtures fo

8、r Con-creteC330 Specification for Lightweight Aggregates for Struc-tural ConcreteC494/C494M Specification for Chemical Admixtures forConcreteC595 Specification for Blended Hydraulic CementsC618 Specification for Coal Fly Ash and Raw or CalcinedNatural Pozzolan for Use in Concrete3. Classification3.1

9、 Precast concrete barriers manufactured in accordancewith this specification shall be as shown in either Fig. 1or Fig.2.4. Basis of Acceptance4.1 Precast barrier shall comply with all of the provisions ofthis specification and shall be tested as prescribed in 8.3 and8.4.4.1.1 Acceptance as to Streng

10、th PropertiesConcrete bar-rier shall be acceptable under the strength tests when thesections have met the requirements of Section 8.4.1.2 Acceptance as to Dimensional PropertiesConcretebarrier shall meet the dimensional tolerances of Section 9.4.1.3 Acceptance as to End ResultThe concrete barriersec

11、tions shall be finally acceptable to the purchaser at thedesignated point of delivery with no significant cracking.Significant cracking is defined as fractures or cracks passingthrough the section or any continuous structural crack extend-ing for a length of 12 in. (305 mm) or more, regardless ofpos

12、ition in the section.5. Materials5.1 CementPortland cement shall conform to the require-ments of Specification C150 or shall be portland blast-furnaceslag cement or portland-pozzolan cement conforming to therequirements of Specification C595.1This specification is under the jurisdiction ofASTM Commi

13、ttee C27 on PrecastConcrete Products and is the direct responsibility of Subcommittee C27.20 onArchitectural and Structural Products.Current edition approved May 1, 2011. Published June 2011. Originallyapproved in 1979. Last previous edition approved in 2006 as C825 06. DOI:10.1520/C0825-06R11.2For

14、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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700,

15、 West Conshohocken, PA 19428-2959, United States.5.2 AggregatesAggregates shall conform to SpecificationC33 or C330.5.3 AdmixturesAdmixtures may be used with the ap-proval of the purchaser. Air-entraining admixtures shall con-form to Specification C260. Chemical admixtures shall con-form to Specific

16、ation C494/C494M. Fly ash or otherpozzolanic admixtures shall conform to Specification C618.Admixtures containing chlorides shall not be used in themanufacture of prestressed barrier sections.5.4 Steel ReinforcementSteel reinforcement shall consistof wire fabric conforming to Specifications A185/A18

17、5M orA497/A497M, or of wire conforming to Specifications A82/A82M, A421/A421M,orA496/A496M, or of strand conform-ing to Specification A416/A416M, or of bars conforming toSpecifications A615/A615M or A996/A996M.6. Design6.1 Precast concrete barrier shall be as defined in Section 3.6.2 Concrete Streng

18、thConcrete for barrier sections shallhave a design compressive strength of 4000 psi (28 MPa) in 28days.6.3 Air EntrainmentUnless otherwise specified by thepurchaser, all concrete shall have an air content of 512 6 1%as measured by Test Methods C173/C173M or C231.6.4 DimensionsCross-sectional dimensi

19、ons of the barriershall be as shown in Fig. 1. Unless otherwise specified by thepurchaser, the length of each barrier section shall be aminimum of 10 ft (3 m).6.5 Steel ReinforcementUnless designated by the pur-chaser, steel reinforcement shall be designed by the producerand shall be sufficient to p

20、ermit handling, delivery, andplacement of the sections without damage. The producer shallprovide steel reinforcement details to the purchaser. The designcover of concrete over reinforcing steel shall be a minimum of2 in. (50 mm). Unless prestressing is used, reinforcement shallbe assembled as a cage

21、 utilizing any combination of single ormultiple layers and mats containing sufficient longitudinal barsor wire extending through the section to maintain the shape andposition of reinforcement within the form during placement ofthe concrete. The exposure of the ends of longitudinal rein-forcement in

22、the barrier shall not be a cause for rejection.NOTE 1The purchaser or producer, or both, of the precast concretebarrier specified herein is cautioned that he should design reinforcing forthe ends of barrier sections in accordance with the publication “ConcreteMedian Barrier Research,” Vol, 2, Resear

23、ch Report, prepared by theSouthwest Research Institute for the Federal Highway Administration, toprevent fracture at the joints.6.6 Reinforcement Laps, Welds, and SplicingAll splicesshall be acceptable to the purchaser and shall develop the fullstrength of the reinforcing.6.7 Concrete FinishConcrete

24、 finishing shall be at theoption of the producer and shall produce a finish comparable toa steel form finish. The concrete finish and curing of all medianbarrier sections shall be uniform for all sections included in thecontract lot.6.8 Lifting DevicesShould the producer cast lifting de-vices into t

25、he barrier sections, they shall not be on the sidesurfaces.6.9 AnchorageAnchorage to prevent lateral movement ofthe barrier shall consist of dowels, keyway joints, or interlock-ing devices as may be specified by the purchaser.7. Manufacture7.1 MixtureThe constituent materials shall be propor-tioned

26、and thoroughly mixed to produce a uniform concretemixture of such quality so as to conform to the strengthrequirements of this specification.7.2 CuringThe barrier section shall be subjected to anyone of the following methods of curing, or combinationthereof. The sections shall be cured for a length

27、of timesufficient to develop the specified concrete compressivestrength as determined in accordance with Section 8.7.2.1 Accelerated CuringThe sections may be cured witheither low-pressure steam or radiant heat in a moist atmo-sphere.7.2.2 Water CuringThe sections may be water-cured bycovering with

28、water-saturated material or by a system ofFIG. 1 New Jersey BarrierFIG. 2 Type-F BarrierC825 06 (2011)2perforated pipes, mechanical sprinklers, porous hose, or by anyother method that will keep the section moist.7.2.3 Membrane CuringA sealing membrane may beapplied at a rate which will restrict the

29、loss of water to not morethan 0.055 g/cm2of surface in 72 h. The concrete at the timeof application shall be within 10F (6C) of the atmospherictemperature. All surfaces shall be kept moist prior to theapplication of the compounds and shall be damp when thecompound is applied.7.2.4 Curing OptionsOthe

30、r methods of curing may beused, if approved by the purchaser.7.3 FormsThe forms used in the manufacture of barriersections shall be sufficiently rigid to maintain productionwithin the permissible tolerances given in Section 9. Allcasting surfaces shall be of smooth nonporous material.8. Physical Req

31、uirements8.1 Compression Test SpecimensThe specimens requiredfor the tests shall be furnished by the producer and shall bemade at random from different batches. Test specimens shall beidentified with barrier sections. Two cylinders will be requiredfor each 25 yd3(19 m3) with a minimum of 2 cylinders

32、 for eachday of production. Compression test specimens for satisfyingthe minimum specified concrete strength requirement shall bemade in accordance with Practice C31/C31M except thatcuring shall be in accordance with 8.2.8.2 Curing Compression Test SpecimensTest specimensshall be cured in a similar

33、manner to barrier sections if they aresteam cured. If barrier sections are cured at normal ambienttemperatures, the specimens shall be cured in accordance withPractice C31/C31M.8.3 Compression TestsCylinders shall be tested in accor-dance with Test Method C39/C39M. The average compressivestrength of

34、 all cylinders tested for each days production shallbe equal to or greater than the specified design strength of theconcrete. In no case shall any cylinder tested fall below 80 %of design strength.8.4 Core Compression TestsIf the criteria of 8.3 are notmet or as an alternative, the producer or purch

35、aser may agreeto use cores taken from the barrier sections in accordance withTest Method C42/C42M. The number of tests required shall beas specified in 8.1. Test results shall conform to 8.3 except thatif cores are used the average compressive ot1 strength of thetest specimens shall be equal to or g

36、reater than 3400 psi (23MPa). No single core shall have a compressive strength lessthan 3000 psi (21 MPa). If the core tests fail on the dailyproduction run, each barrier section may be individually coredfor acceptance.9. Permissible Dimensional Tolerances9.1 Cross-Sectional DimensionsCross-sectiona

37、l dimen-sions shall not vary from design dimensions by more than14 in.(6 mm). The vertical center line shall not be out of plumb bymore than14 in. (6 mm).9.2 Longitudinal DimensionsLongitudinal dimensionsshall not vary from the design dimensions by more than14 in.(6 mm) per 10 ft (3 m) of barrier se

38、ction and shall not exceed34 in. (19 mm) per section.9.3 Location of Anchoring DevicesLocation of anchoringholes shall be as specified by the purchaser.9.4 Surface StraightnessWhen checked with a 10-ft (3-m)straight edge, irregularities measuring more than14 in. (6 mm)shall be corrected as the purch

39、aser may order or approve.9.5 Position of ReinforcementCover over reinforcementshall be not less than 2 in. (50 mm), except for longitudinalreinforcement at the end face of barrier sections.10. Inspection10.1 The quality of materials, the process of manufacturing,and the finished median barrier shal

40、l be available for inspectionby an inspector employed by the purchaser. If the manufactureris required to obtain the services of an independent testingagency, the costs shall be the purchasers responsibility.11. Repairs11.1 Barrier sections may be repaired, if necessary, becauseof occasional imperfe

41、ctions in manufacture or damage duringhandling. They shall be acceptable if, in the opinion of thepurchaser, the repairs are sound, properly finished, and cured.The repaired sections shall conform to the requirements of thisspecification. Repairs to correct imperfections in manufactureor damage duri

42、ng handling may be made only after authoriza-tion by the purchaser.12. Rejection12.1 Barrier sections shall be subject to rejection for failureto conform to any of the specification requirements. In addi-tion, individual sections may be rejected due to defects thatindicate inadequate proportioning,

43、mixing, or molding.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 expressly advised that determination of the validity of any such patent rights, and the riskof infringement

44、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 revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for

45、 additional standardsand should be addressed 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

46、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 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). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).C825 06 (2011)3