1、Designation: C478M 15Standard Specification forCircular Precast Reinforced Concrete Manhole Sections(Metric)1This standard is issued under the fixed designation C478M; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of las
2、t revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.PART IGENERAL1. Scope1.1 This specification cov
3、ers the manufacture and purchaserequirements of products used for the assembly and construc-tion of circular vertical precast reinforced concrete manholesand structures used in sewer, drainage, and water works.1.2 Part I, Sections 111, of this specification presentsgeneral requirements and requireme
4、nts which are common toeach precast concrete product covered by this specification.1.3 Part II of this specification presents specific require-ments for each manhole product in the following sections:Product SectionGrade Rings 12Flat Slab Tops 13Risers and Conical Tops 14Base Sections 15Steps and La
5、dders 16NOTE 1Future products will be included in Part II in a future revisionof this specification.1.4 This specification is the SI companion to C478.NOTE 2This specification is a manufacturing and purchase specifica-tion only, and does not include requirements for backfill, or the relation-ship be
6、tween field load conditions and the strength requirements of themanhole products and appurtenances. Experience has shown, however,that the successful performance of this product depends upon the properselection of the product strength, type of foundation and backfill, and carein the field installati
7、on of the manhole products and connecting pipes. Theowner of the project for which these products are specified herein iscautioned to require inspection at the construction site.2. Referenced Documents2.1 ASTM Standards:2A615/A615M Specification for Deformed and Plain Carbon-Steel Bars for Concrete
8、ReinforcementA706/A706M Specification for Deformed and Plain Low-Alloy Steel Bars for Concrete ReinforcementA1064/A1064M Specification for Carbon-Steel Wire andWelded Wire Reinforcement, Plain and Deformed, forConcreteC33 Specification for Concrete AggregatesC39/C39M Test Method for Compressive Stre
9、ngth of Cylin-drical Concrete SpecimensC150 Specification for Portland CementC260 Specification for Air-Entraining Admixtures for Con-creteC309 Specification for Liquid Membrane-Forming Com-pounds for Curing ConcreteC494/C494M Specification for Chemical Admixtures forConcreteC497 Test Methods for Co
10、ncrete Pipe, Manhole Sections, orTileC595 Specification for Blended Hydraulic CementsC618 Specification for Coal Fly Ash and Raw or CalcinedNatural Pozzolan for Use in ConcreteC822 Terminology Relating to Concrete Pipe and RelatedProductsC989 Specification for Slag Cement for Use in Concrete andMort
11、arsC1017/C1017M Specification for Chemical Admixtures forUse in Producing Flowing ConcreteC1602/C1602M Specification for Mixing Water Used in theProduction of Hydraulic Cement Concrete2.2 ACI Standard:ACI 318 Building Code, Requirements for Reinforced Con-crete33. Terminology3.1 DefinitionsFor defin
12、itions of terms relating to concretepipe, see Terminology C822.1This specification is under the jurisdiction of ASTM Committee C13 onConcrete Pipe and is the direct responsibility of Subcommittee C13.06 on Manholesand Specials.Current edition approved Jan. 1, 2015. Published January 2015. Originally
13、approved in 1980. Last previous edition approved in 2014 as C478M 14. DOI:10.1520/C0478M-15.2For 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 S
14、ummary page onthe ASTM website.3Available from American Concrete Institute (ACI), P.O. Box 9094, FarmingtonHills, MI 48333-9094, http:/www.aci-int.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Materials and Manufacture4.1 Gen
15、eral material requirements for precast reinforcedconcrete manhole products are presented in 4.1.1 4.1.9. Othermaterials or additional requirements for a product, if any, arecovered in the Part II section for that specific product.4.1.1 Reinforced ConcreteReinforced concrete shall con-sist of cementi
16、tious materials, mineral aggregates, and water, inwhich steel reinforcement has been embedded in such amanner so that the steel reinforcement and concrete acttogether.4.1.2 Cementitious Materials:4.1.2.1 CementCement shall conform to the requirementsfor portland cement of Specification C150, or shal
17、l be portlandblast-furnace slag cement or portland-pozzolan cement con-forming to Specification C595, except that the pozzolanconstituent of the Type IP portland-pozzolan cement shall befly ash.4.1.2.2 Fly AshFly ash shall conform to the requirementsof Class F or Class C of Specification C618.4.1.2.
18、3 Slag CementSlag cement shall conform to therequirements of Grade 100 or 120 of Specification C989.4.1.3 Allowable Combinations of Cementitious MaterialsThe combination of cementitious materials used in the concreteshall be one of the following:4.1.3.1 Portland cement only,4.1.3.2 Portland blast-fu
19、rnace slag cement only,4.1.3.3 Portland pozzolan cement only,4.1.3.4 A combination of Portland cement and slag cement,4.1.3.5 A combination of Portland cement and fly ash, or4.1.3.6 A combination of Portland cement, slag cement (notto exceed 25 % of the total cementitious weight) and fly ash(not to
20、exceed 25 % of the total cementitious weight).4.1.4 AggregatesAggregates shall conform to Specifica-tion C33, except that the requirements for gradation shall notapply.4.1.5 Admixtures and BlendsThe following admixturesand blends are allowable:4.1.5.1 Air-entraining admixture conforming to Specifica
21、-tion C260;4.1.5.2 Chemical admixture conforming to SpecificationC494/C494M;4.1.5.3 Chemical admixture for use in producing flowingconcrete conforming to Specification C1017/C1017M;4.1.5.4 Chemical admixture or blend approved by theowner.4.1.6 Steel ReinforcementReinforcement shall consist ofwire an
22、d welded wire conforming to Specification A1064/A1064M; or of bars conforming to Specification A615/A615M, Grade 280 or 420, or Specification A706/A706M,Grade 420.4.1.7 WaterWater used in the production of concrete shallbe potable or non-potable water that meets the requirements ofSpecification C160
23、2/C1602M.4.1.8 Secondary Synthetic FiberCollated fibrillated poly-propylene virgin fibers shall not be prohibited when used insteel reinforced concrete manholes as a non-structural manu-facturing enhancement. Only fibers designed and manufacturedspecifically for use in concrete and so certified by t
24、he manu-facturer shall be accepted.4.1.9 Other MaterialsOther materials required for a prod-uct and not covered in Section 4 will be covered in the Part IIsection for that specific product.5. Design5.1 Design requirements for a product are prescribed in thespecific Part II section for that product.5
25、.1.1 The minimum compressive strength of concrete man-hole products covered by this specification shall be 27.6 MPaunless specified otherwise in Part II of this specification.5.2 Modified or Special Design:5.2.1 Manufacturers are not prohibited from submitting tothe owner, for approval prior to manu
26、facture, designs otherthan those prescribed in the specific section for a product. Ifsuch approval is obtained, then the product shall meet all thetests and performance requirements specified by the owner inaccordance with the appropriate sections on manufacture andphysical requirements.5.2.2 If per
27、mitted by the owner, the manufacturer is notprohibited from requesting approval of designs of specialsections, such as reducers, tees, and bases.6. Reinforcement6.1 This section presents requirements for reinforcementcover, continuity, laps, welds and splices. Other reinforcementrequirements are pre
28、sented in Section 4 and any additionalrequirements are given in the Part II section for a specificproduct.6.2 CoverThe exposure of the ends of reinforcement,stirrups or spacers used to position the reinforcement duringplacement of the concrete shall not be cause for rejection.6.3 ContinuityThe conti
29、nuity of the circumferential rein-forcement shall not be destroyed during the manufacture of theproduct, except when lift holes or pipe openings are providedin the product.6.4 Welded Steel Cage Laps. Welds, and Splices:6.4.1 If splices are not welded, the reinforcement shall belapped not less than 2
30、0 diameters for deformed bars, and 40diameters for plain bars and cold-drawn wire. In addition,where lapped cages of welded wire fabric are used withoutwelding, the lap shall contain a longitudinal wire.6.4.2 When splices are welded and are not lapped to theminimum requirements in 6.4.1, there shall
31、 be a minimum lapof 50 mm and a weld of sufficient length such that pull tests ofrepresentative specimens shall develop at least 50 % of theminimum specified tensile strength of the steel. For buttwelded splices in bars or wire, permitted only with helicallywound cages, pull tests of representative
32、specimens shalldevelop at least 75 % of the minimum specified tensile strengthof the steel.6.5 Steel Hoop SplicesWhen splices are welded and notlapped to the minimum requirements in 6.4.1, there shall be aminimum lap of 50 mm and a weld of sufficient length suchthat pull tests from representative sp
33、ecimens shall develop atleast 50 % of the minimum specified tensile strength of theC478M 152steel. For butt welded splices, pull tests from representativespecimens shall develop at least 75 % of the minimum speci-fied tensile strength of the steel.7. Precast Concrete Manufacture7.1 MixtureThe aggreg
34、ates shall be sized, graded,proportioned, and mixed with such proportions of cementitiousmaterials and water as will produce a thoroughly-mixedconcrete of such quality that the products will conform to thetest and design requirements of this specification. All concreteshall have a water-cementitious
35、 ratio not exceeding 0.53 bymass. Cementitious materials shall be as specified in 4.1.2 andshall be added to the mix in a proportion not less than 280kg/m3, unless mix designs with a lower cementitious materialscontent demonstrate that the quality and performance of theproduct meet the requirements
36、of this specification.7.2 CuringConcrete products shall be subjected to anyone of the methods of curing prescribed in 7.2.1 7.2.4 or toany other method or combination of methods approved by theowner that will give satisfactory results.7.2.1 Steam CuringConcrete products are placed in acuring chamber
37、, free of outside drafts, and cured in a moistatmosphere maintained by the injection of steam for such timeand such temperatures as may be needed to enable the productsto meet the strength requirements. The curing chamber shall beso constructed as to allow full circulation of the steam aroundthe ent
38、ire product.7.2.2 Water CuringConcrete products are water-cured bycovering with water-saturated material, or by a system ofperforated pipes, mechanical sprinklers, porous hose, or by anyother approved method that will keep the products moist duringthe curing period.7.2.3 Sealing MembraneA sealing me
39、mbrane conformingto the requirements of Specification C309 is applied and shallbe left intact until the required concrete strength requirementsare met. The concrete at the time of application of themembrane shall be within 6C of the atmospheric temperature.All concrete surfaces shall be kept moist p
40、rior to the applica-tion of the membrane and shall be damp when the membraneis applied.7.2.4 The manufacturer is not prohibited from combiningmethods prescribed in 7.2.1 7.2.3 provided the requiredconcrete compressive strength is attained.8. Acceptance8.1 Acceptance Procedures:8.1.1 Unless otherwise
41、 designated by the owner at the timeof, or before, placing an order, acceptance procedures forprecast reinforced concrete manhole products shall be asspecified in the Part II section for a particular product, and shallnot be prohibited from consisting of one or more of thefollowing:8.1.1.1 Acceptanc
42、e of a product on the basis of tests ofmaterials, including concrete compressive strength and absorp-tion.8.1.1.2 Acceptance of a product on the basis of inspection ofthe finished product, including amount and placement ofreinforcement to determine conformance with the designprescribed under this sp
43、ecification, and freedom from defects.8.2 Test Methods:8.2.1 Concrete Compressive Strength Test:8.2.1.1 Type of SpecimenCompression tests for satisfyingthe minimum specified concrete strength requirement shall bemade on either concrete cylinders or, at the option of themanufacturer, on cores cut fro
44、m the concrete manhole product.8.2.1.2 Compression Testing of CylindersCylinders shallbe made in accordance with Test Methods C497, and shall betested in accordance with Test Method C39/C39M. For man-hole products, an owner shall not be prohibited from requiringconcrete compressive tests on cylinder
45、 specimens numberingin the amount of 5 % of the total order of a manhole product,but not to exceed two cylinders for each days production. Theaverage compressive strength of all cylinders tested shall beequal to or greater than the specified strength of the concrete.Not more than 10 % of the cylinde
46、rs tested shall fall below thespecified strength of the concrete. In no case shall any cylindertested fall below 80 % of the specified strength of the concrete.8.2.1.3 Compression Testing of CoresCores shall be cutfrom the concrete manhole product and tested in accordancewith Test Methods C497, exce
47、pt that the requirements formoisture conditioning shall not apply. One core shall be takenfrom a manhole product selected at random from each daysproduction run of a single concrete strength. When the concretecompressive strength of the core is equal to or greater than80 % of the specified strength
48、of the concrete, the concretestrength of the production run is acceptable. If the core doesnot meet the preceding concrete strength requirement, anothercore from the same manhole product may be taken and tested.8.2.1.4 If the concrete compressive strength of the recore isequal to or greater than 80
49、% of the specified strength of theconcrete, the concrete strength of the production run is accept-able. If the recore does not meet the preceding concretestrength requirement, that manhole product shall be rejected.Two manhole products from the remainder of the daysproduction run shall be selected at random and one core takenfrom each manhole product and tested. When the averageconcrete strength of the two cores is equal to or greater than80 % of the specified strength of the concrete with no corebelow 75 % of the specified strength of the concr
