1、Designation: C478M 15aC478M 18Standard 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 ye
2、ar of last 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 specific
3、ation covers the manufacture and purchase requirements of products used for the assembly and construction ofcircular vertical precast reinforced concrete manholes and structures used in sewer, drainage, and water works.1.2 Part I, Sections 1 11, of this specification presents general requirements an
4、d requirements which are common to eachprecast concrete product covered by this specification.1.3 Part II of this specification presents specific requirements for each manhole product in the following sections:Product SectionGrade Rings 12Flat Slab Tops 13Risers and Conical Tops 14Base Sections 15St
5、eps and Ladders 16NOTE 1Future products will be included in Part II in a future revision of this specification.1.4 This specification is the SI companion to C478.NOTE 2This specification is a manufacturing and purchase specification only, and does not include requirements for backfill, or the relati
6、onshipbetween field load conditions and the strength requirements of the manhole products and appurtenances. Experience has shown, however, that thesuccessful performance of this product depends upon the proper selection of the product strength, type of foundation and backfill, and care in the field
7、installation of the manhole products and connecting pipes. The owner of the project for which these products are specified herein is cautioned to requireinspection at the construction site.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It i
8、s the responsibilityof the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability ofregulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standa
9、rdizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2A615/A615M Specification for Deformed and Plain C
10、arbon-Steel Bars for Concrete ReinforcementA706/A706M Specification for Deformed and Plain Low-Alloy Steel Bars for Concrete ReinforcementA1064/A1064M Specification for Carbon-Steel Wire and Welded Wire Reinforcement, Plain and Deformed, for ConcreteC33/C33M Specification for Concrete AggregatesC39/
11、C39M Test Method for Compressive Strength of Cylindrical Concrete SpecimensC150/C150M Specification for Portland CementC260/C260M Specification for Air-Entraining Admixtures for Concrete1 This specification is under the jurisdiction ofASTM Committee C13 on Concrete Pipe and is the direct responsibil
12、ity of Subcommittee C13.06 on Manholes and Specials.Current edition approved Oct. 15, 2015Jan. 1, 2018. Published November 2015January 2018. Originally approved in 1980. Last previous edition approved in 2015 asC478M 15.C478M 15a. DOI: 10.1520/C0478M-15A.10.1520/C0478M-18.2 For referencedASTM standa
13、rds, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an AST
14、M standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published
15、by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1C309 Specification for Liquid Membrane-Forming Compounds for Curing ConcreteC494/C494M Specification for Chemical Admixtures for Concret
16、eC497M Test Methods for Concrete Pipe, Manhole Sections, or Tile (Metric)C595/C595M Specification for Blended Hydraulic CementsC618 Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in ConcreteC822 Terminology Relating to Concrete Pipe and Related ProductsC989/C989M Specifi
17、cation for Slag Cement for Use in Concrete and MortarsC1017/C1017M Specification for Chemical Admixtures for Use in Producing Flowing ConcreteC1116/C1116M Specification for Fiber-Reinforced ConcreteC1602/C1602M Specification for Mixing Water Used in the Production of Hydraulic Cement Concrete2.2 ACI
18、 Standard:ACI 318 Building Code, Requirements for Reinforced Concrete33. Terminology3.1 DefinitionsFor definitions of terms relating to concrete pipe, see Terminology C822.4. Materials and Manufacture4.1 General material requirements for precast reinforced concrete manhole products are presented in
19、4.1.1 4.1.9. Othermaterials or additional requirements for a product, if any, are covered in the Part II section for that specific product.4.1.1 Reinforced ConcreteReinforced concrete shall consist of cementitious materials, mineral aggregates, admixtures, ifused, and water, in which steel reinforce
20、ment has been embedded in such a manner so that the steel reinforcement and concreteact together.4.1.2 Cementitious Materials:4.1.2.1 CementCement shall conform to the requirements for portland cement of Specification C150/C150M, or shall beportland blast-furnace slag cement, portland-limestone ceme
21、nt, or portland-pozzolan cement conforming to the requirements ofSpecification C595/C595M, except that the pozzolan constituent of the Type IP portland-pozzolan cement shall be fly ash.4.1.2.2 Fly AshFly ash shall conform to the requirements of Class F or Class C of Specification C618.4.1.2.3 Slag C
22、ementSlag cement shall conform to the requirements of Grade 100 or 120 of Specification C989/C989M.4.1.3 Allowable Combinations of Cementitious MaterialsThe combination of cementitious materials used in the concrete shallbe one of the following:4.1.3.1 Portland cement only,4.1.3.2 Portland blast-fur
23、nace slag cement only,4.1.3.3 Portland-pozzolan cement only,4.1.3.4 Portland-limestone cement only,4.1.3.5 A combination of portland cement or portland-limestone cement and slag cement,4.1.3.6 A combination of portland cement or portland-limestone cement and fly ash,4.1.3.7 A combination of portland
24、 cement or portland-limestone cement, slag cement, and fly ash, or4.1.3.8 A combination of portland-pozzolan cement and fly ash.4.1.4 AggregatesAggregates shall conform to Specification C33/C33M, except that the requirements for gradation shall notapply.4.1.5 AdmixturesThe following admixtures and b
25、lends are allowable:4.1.5.1 Air-entraining admixture conforming to Specification C260/C260M;4.1.5.2 Chemical admixture conforming to Specification C494/C494M;4.1.5.3 Chemical admixture for use in producing flowing concrete conforming to Specification C1017/C1017M;4.1.5.4 Chemical admixture or blend
26、approved by the owner.4.1.6 Steel ReinforcementReinforcement shall consist of wire and 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
27、shall be potable or non-potable water that meets the requirements ofSpecification C1602/C1602M.4.1.8 FiberSynthetic fibers and nonsynthetic fibers shall be allowed to be used, at the manufacturers option, in concretemanholes as a nonstructural manufacturing material. Synthetic fibers (Type II and Ty
28、pe III) and nonsynthetic fiber (Type 1)designed and manufactured specifically for use in concrete and conforming to the requirements of Specification C1116/C1116Mshall be accepted.4.1.9 Other MaterialsOther materials required for a product and not covered in Section 4 will be covered in the Part II
29、sectionfor that specific product.3 Available from American Concrete Institute (ACI), P.O. Box 9094, Farmington Hills, MI 48333-9094, http:/www.aci-int.org.C478M 1825. Design5.1 Design requirements for a product are prescribed in the specific Part II section for that product.5.1.1 The minimum compres
30、sive strength of concrete manhole products covered by this specification shall be 27.6 MPa unlessspecified otherwise in Part II of this specification.5.2 Modified or Special Design:5.2.1 Manufacturers are not prohibited from submitting to the owner, for approval prior to manufacture, designs other t
31、han thoseprescribed in the specific section for a product. If such approval is obtained, then the product shall meet all the tests andperformance requirements specified by the owner in accordance with the appropriate sections on manufacture and physicalrequirements.5.2.2 If permitted by the owner, t
32、he manufacturer is not prohibited from requesting approval of designs of special sections, suchas reducers, tees, and bases.6. Reinforcement6.1 This section presents requirements for reinforcement cover, continuity, laps, welds and splices. Other reinforcementrequirements are presented in Section 4
33、and any additional requirements are given in the Part II section for a specific product.6.2 CoverThe exposure of the ends of reinforcement, stirrups or spacers used to position the reinforcement during placementof the concrete shall not be cause for rejection.6.3 ContinuityThe continuity of the circ
34、umferential reinforcement shall not be destroyed during the manufacture of theproduct, except when lift holes or pipe openings are provided in the product.6.4 Welded Steel Cage Laps. Welds, and Splices:6.4.1 If splices are not welded, the reinforcement shall be lapped not less than 20 diameters for
35、deformed bars, and 40 diametersfor plain bars and cold-drawn wire. In addition, where lapped cages of welded wire fabric are used without welding, the lap shallcontain a longitudinal wire.6.4.2 When splices are welded and are not lapped to the minimum requirements in 6.4.1, there shall be a minimum
36、lap of 50mm and a weld of sufficient length such that pull tests of representative specimens shall develop at least 50 % of the minimumspecified tensile strength of the steel. For butt welded splices in bars or wire, permitted only with helically wound cages, pull testsof representative specimens sh
37、all develop at least 75 % of the minimum specified tensile strength of the steel.6.5 Steel Hoop SplicesWhen splices are welded and not lapped to the minimum requirements in 6.4.1, there shall be aminimum lap of 50 mm and a weld of sufficient length such that pull tests from representative specimens
38、shall develop at least50 % of the minimum specified tensile strength of the steel. For butt welded splices, pull tests from representative specimens shalldevelop at least 75 % of the minimum specified tensile strength of the steel.7. Precast Concrete Manufacture7.1 MixtureThe aggregates shall be siz
39、ed, graded, proportioned, and mixed with such proportions of cementitious materialsand water as will produce a thoroughly-mixed concrete of such quality that the products will conform to the test and designrequirements of this specification. All concrete shall have a water-cementitious ratio not exc
40、eeding 0.53 by mass. Cementitiousmaterials shall be as specified in 4.1.2 and shall be added to the mix in a proportion not less than 280 kg/m3, unless mix designswith a lower cementitious materials content demonstrate that the quality and performance of the product meet the requirementsof this spec
41、ification.7.2 CuringConcrete products shall be subjected to any one of the methods of curing prescribed in 7.2.1 7.2.4 or to any othermethod or combination of methods approved by the owner that will give satisfactory results.7.2.1 Steam CuringConcrete products are placed in a curing chamber, free of
42、 outside drafts, and cured in a moist atmospheremaintained by the injection of steam for such time and such temperatures as may be needed to enable the products to meet thestrength requirements. The curing chamber shall be so constructed as to allow full circulation of the steam around the entirepro
43、duct.7.2.2 Water CuringConcrete products are water-cured by covering with water-saturated material, or by a system of perforatedpipes, mechanical sprinklers, porous hose, or by any other approved method that will keep the products moist during the curingperiod.7.2.3 Sealing MembraneA sealing membran
44、e conforming to the requirements of Specification C309 is applied and shall beleft intact until the required concrete strength requirements are met. The concrete at the time of application of the membrane shallbe within 6C of the atmospheric temperature. All concrete surfaces shall be kept moist pri
45、or to the application of the membraneand shall be damp when the membrane is applied.7.2.4 The manufacturer is not prohibited from combining methods prescribed in 7.2.1 7.2.3 provided the required concretecompressive strength is attained.C478M 1838. Acceptance8.1 Acceptance Procedures:8.1.1 Unless ot
46、herwise designated by the owner at the time of, or before, placing an order, acceptance procedures for precastreinforced concrete manhole products shall be as specified in the Part II section for a particular product, and shall not be prohibitedfrom consisting of one or more of the following:8.1.1.1
47、 Acceptance of a product on the basis of tests of materials, including concrete compressive strength and absorption.8.1.1.2 Acceptance of a product on the basis of inspection of the finished product, including amount and placement ofreinforcement to determine conformance with the design prescribed u
48、nder this specification, and freedom from defects.8.2 Test Methods:8.2.1 Concrete Compressive Strength Test:8.2.1.1 Type of SpecimenCompression tests for satisfying the minimum specified concrete strength requirement shall be madeon either concrete cylinders or, at the option of the manufacturer, on
49、 cores cut from the concrete manhole product.8.2.1.2 Compression Testing of CylindersCylinders shall be made in accordance with Test Methods C497M, and shall betested in accordance with Test Method C39/C39M. For manhole products, an owner shall not be prohibited from requiring concretecompressive tests on cylinder specimens numbering in the amount of 5 % of the total order of a manhole product, but not to exceedtwo cylinders for each days production. The average compressive strength of all cylinders tested shall be equal to or greater thant
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