1、Designation: C478 15aC478 18Standard Specification forCircular Precast Reinforced Concrete Manhole Sections1This standard is issued under the fixed designation C478; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、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 cover
3、s 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 and requireme
4、nts that are common to each precastconcrete 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 15Steps and Ladd
5、ers 16NOTE 1Future products will to be included in Part II in a future revision of this specification.1.4 This specification is the inch-pound companion to Specification C478M; therefore, no SI equivalents are presented in thespecification.NOTE 2This specification is a manufacturing and purchase spe
6、cification only and does not include requirements for backfill, or the relationshipbetween 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
7、 the product strength, type of foundation and backfill, and care in the fieldinstallation 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
8、 to address all of the safety concerns, if any, associated with its use. It is 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
9、 developed in accordance with internationally recognized principles on standardizationestablished 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.1 This specific
10、ation is under the jurisdiction ofASTM Committee C13 on Concrete Pipe and is the direct responsibility of Subcommittee C13.06 on Manholes and Specials.Current edition approved Oct. 15, 2015Jan. 1, 2018. Published November 2015January 2018. Originally approved in 1961. Last previous edition approved
11、in 2015 asC478 15.C478 15a. DOI: 10.1520/C0478-15A.10.1520/C0478-18.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict
12、all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-
13、2959. United States12. Referenced Documents2.1 ASTM Standards:2A615/A615M Specification for Deformed and Plain Carbon-Steel Bars for Concrete ReinforcementA706/A706M Specification for Deformed and Plain Low-Alloy Steel Bars for Concrete ReinforcementA1064/A1064M Specification for Carbon-Steel Wire a
14、nd Welded Wire Reinforcement, Plain and Deformed, for ConcreteC33/C33M Specification for Concrete AggregatesC39/C39M Test Method for Compressive Strength of Cylindrical Concrete SpecimensC150/C150M Specification for Portland CementC260/C260M Specification for Air-Entraining Admixtures for ConcreteC3
15、09 Specification for Liquid Membrane-Forming Compounds for Curing ConcreteC494/C494M Specification for Chemical Admixtures for ConcreteC497 Test Methods for Concrete Pipe, Manhole Sections, or TileC595/C595M Specification for Blended Hydraulic CementsC618 Specification for Coal Fly Ash and Raw or Ca
16、lcined Natural Pozzolan for Use in ConcreteC822 Terminology Relating to Concrete Pipe and Related ProductsC989/C989M Specification for Slag Cement for Use in Concrete and MortarsC1017/C1017M Specification for Chemical Admixtures for Use in Producing Flowing ConcreteC1116/C1116M Specification for Fib
17、er-Reinforced ConcreteC1602/C1602M Specification for Mixing Water Used in the Production of Hydraulic Cement Concrete2.2 ACI Standard:3318 Building Code, Requirements for Reinforced Concrete3. Terminology3.1 DefinitionsFor definitions of terms relating to precast reinforced concrete manholes, see Te
18、rminology C822.4. Materials and Manufacture4.1 General material requirements for precast reinforced concrete manhole products are presented in 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 C
19、oncreteReinforced concrete shall consist of cementitious materials, mineral aggregates, admixtures, ifused, and water, in which steel reinforcement 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 conf
20、orm to the requirements for portland cement of Specification C150/C150M, or shall beportland blast-furnace slag cement, portland-limestone cement, or portland-pozzolan cement conforming to the requirements ofSpecification C595/C595M, except that the pozzolan constituent of the Type IP portland-pozzo
21、lan 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 CementSlag cement shall conform to the requirements of Grade 100 or 120 of Specification C989/C989M.4.1.3 Allowable Combinations of Cementitious MaterialsThe
22、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-furnace 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-limes
23、tone cement and slag cement,4.1.3.6 A combination of portland cement or portland-limestone cement, and fly ash, or4.1.3.7 A combination of portland 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 AggregatesAggregate
24、s shall conform to Specification C33/C33M, except that the requirements for gradation shall notapply.4.1.5 AdmixturesThe following admixtures and blends are allowable:4.1.5.1 Air-entraining admixture conforming to Specification C260/C260M;4.1.5.2 Chemical admixture conforming to Specification C494/C
25、494M;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 approved by the owner.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. ForAnnual
26、Book ofASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from American Concrete Institute (ACI), P.O. Box 9094, Farmington Hills, MI 48333-9094, http:/www.aci-int.org.C478 1824.1.6 Steel ReinforcementReinforcement shall consist of wire and
27、 welded wire conforming to Specification A1064/A1064Mor of bars conforming to Specification A615/A615M, Grade 40 or 60, or Specification A706/A706M, Grade 60.4.1.7 WaterWater used in the production of concrete shall be potable or non-potable water that meets the requirements ofSpecification C1602/C1
28、602M.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 Type III) and nonsynthetic fiber (Type 1)designed and manufactured specifically for use in c
29、oncrete 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 sectionfor that specific product.5. Design5.1 Design requirements for a product are prescr
30、ibed in the specific Part II section for that product.5.1.1 The minimum compressive strength of concrete manhole products covered by this specification shall be 4000 psi unlessspecified otherwise in Part II of this specification.5.2 Modified or Special Design5.2.1 Manufacturers are not prohibited fr
31、om submitting to the owner, for approval prior to manufacture, designs other than 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 secti
32、ons on manufacture and physicalrequirements.5.2.2 If permitted by the owner, the 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,
33、welds, and splices. Other reinforcementrequirements are presented in Section 4, 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 co
34、ncrete shall not be cause for rejection.6.3 ContinuityThe continuity of the circumferential 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 a
35、re not welded, the reinforcement shall be lapped not less than 20 diameters for 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 an
36、d are not lapped to the minimum requirements in 6.4.1, there shall be a minimum lap of 2 in.and a weld of sufficient length such that pull tests of representative specimens shall develop at least 50 % of the minimum specifiedtensile strength of the steel. For butt welded splices in bars or wire, per
37、mitted only with helically wound cages, pull tests ofrepresentative specimens shall develop at least 75 % of the minimum specified tensile strength of the steel.6.5 Steel Hoop SplicesWhen splices are welded and are not lapped to the minimum requirements in 6.4.1, there shall be aminimum lap of 2 in.
38、 and a weld of sufficient length such that pull tests from representative specimens shall develop at least 50 %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 strengt
39、h of the steel.7. Precast Concrete Manufacture7.1 MixtureThe aggregates shall be sized, 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 designrequiremen
40、ts of this specification. All concrete shall have a water-cementitious ratio not exceeding 0.53 by weight. Cementitiousmaterials shall be as specified in 4.1.2 and shall be added to the mix in a proportion not less than 470 lb/yd3, unless mix designswith a lower cementitious materials content demons
41、trate that the quality and performance of the product meet the requirementsof this specification.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 satisfact
42、ory results.7.2.1 Steam CuringConcrete products are placed in a curing chamber, free of outside drafts, and cured in a moist atmospheremaintained by the injection of steam for such time and such temperatures as needed to enable the products to meet the strengthrequirements. The curing chamber shall
43、be so constructed as to allow full circulation of the steam around the entire product.C478 1837.2.2 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 wil
44、l keep the products moist during the curingperiod.7.2.3 Sealing MembraneA sealing membrane 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 shallb
45、e within 10F of the atmospheric temperature. All concrete surfaces shall be kept moist prior to the application of the membraneand shall be damp when the membrane is applied.7.2.4 The manufacturer is not prohibited from combining the methods prescribed in 7.2.1 7.2.3 provided the required concreteco
46、mpressive strength is attained.8. Acceptance8.1 Acceptance Procedures:8.1.1 Unless otherwise 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 produc
47、t, and shall not be prohibitedfrom consisting of one or more of the following:8.1.1.1 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 amoun
48、t and placement ofreinforcement to determine conformance with the design prescribed under 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 requiremen
49、t shall be madeon either concrete cylinders or, at the option of the manufacturer, on cores cut from the concrete manhole product.8.2.1.2 Compression Testing of CylindersCylinders shall be made in accordance with Test Methods C497, and shall be testedin 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 ave
