1、Designation: C858 101Standard Specification forUnderground Precast Concrete Utility Structures1This standard is issued under the fixed designation C858; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A n
2、umber in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTEAir entrainment admixture information was moved editorially from subsection 5.3.3 to subsection 6.3.2in November 2010.1. Scope1.1 This specific
3、ation covers the recommended design cri-teria and manufacturing practices for monolithic or sectionalprecast concrete utility structures. Concrete pipe and boxculverts are not covered under this specification. Also, precastconcrete manholes covered in Specification C478 are excludedfrom this specifi
4、cation.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 Specification for Steel Wi
5、re, Plain, for ConcreteReinforcementA184/A184M Specification for Welded Deformed Steel BarMats for Concrete ReinforcementA185/A185M Specification for Steel Welded Wire Rein-forcement, Plain, for ConcreteA496/A496M Specification for Steel Wire, Deformed, forConcrete ReinforcementA497/A497M Specificat
6、ion for Steel Welded Wire Rein-forcement, Deformed, for ConcreteA615/A615M Specification for Deformed and PlainCarbon-Steel Bars for Concrete ReinforcementA706/A706M Specification for Low-Alloy Steel Deformedand Plain Bars for Concrete ReinforcementA996/A996M Specification for Rail-Steel and Axle-St
7、eelDeformed 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 DrilledCores a
8、nd Sawed Beams of ConcreteC94/C94M Specification for Ready-Mixed ConcreteC150 Specification for Portland CementC192/C192M Practice for Making and Curing ConcreteTest Specimens in the LaboratoryC231 Test Method for Air Content of Freshly Mixed Con-crete by the Pressure MethodC260 Specification for Ai
9、r-Entraining Admixtures for Con-creteC330 Specification for Lightweight Aggregates for Struc-tural ConcreteC478 Specification for Precast Reinforced Concrete Man-hole SectionsC494/C494M Specification for Chemical Admixtures forConcreteC595 Specification for Blended Hydraulic CementsC618 Specificatio
10、n for Coal Fly Ash and Raw or CalcinedNatural Pozzolan for Use in ConcreteC857 Practice for Minimum Structural Design Loading forUnderground Precast Concrete Utility StructuresC989 Specification for Slag Cement for Use in Concreteand Mortars2.2 American Concrete Institute Standard:ACI 318 Building C
11、ode Requirements for Reinforced Con-crete32.3 American Welding Society Standard:AWS-D1.4 Structural Welding Code Reinforcing Steel43. Terminology3.1 Definition of Term Specific to this Standard:3.1.1 utility structurea structure that is used by electric,gas, communication, or similar industries.1Thi
12、s specification is under the jurisdiction ofASTM Committee C27 on PrecastConcrete Products and is the direct responsibility of Subcommittee C27.10 onUtility Structures.Current edition approved Feb. 15, 2010. Published February 2010. Originallyapproved in 1978. Last previous edition approved in 2009
13、as C858 09. DOI:10.1520/C0858-10E01.2For 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 Summary page onthe ASTM website.3Available from American
14、Concrete Institute (ACI), P.O. Box 9094, FarmingtonHills, MI 48333-9094, http:/www.aci-int.org.4Available from American Welding Society (AWS), 550 NW LeJeune Rd.,Miami, FL 33126, http:/www.aws.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, Un
15、ited States.4. Ordering Information4.1 Unless otherwise stipulated by the purchaser in hisorder, a structure produced in accordance with this specifica-tion and constructed in accordance with the design drawingsapproved by the purchaser shall be acceptable.5. Materials5.1 Cementitious Materials:5.1.
16、1 CementCement shall conform to the requirementsfor Portland cement of Specification C150 or shall be Portlandblast-furnace slag cement or Portland-pozzolan cement con-forming to the requirements of Specification C595, except thatthe pozzolan constituent in the Type IP Portland-pozzolancement shall
17、be fly ash.5.1.2 Fly AshFly ash shall conform to the requirementsof Specification C618, Class F or Class C.5.1.3 Ground Granulated Blast-Furnace Slag (GGBFS)GGBFS shall conform to the requirements of Grade 100 or 120of Specification C989.5.1.4 Allowable Combinations of Cementitious MaterialThe combi
18、nation of cementitious materials used in concreteshall be one of the following:5.1.4.1 Portland cement only;5.1.4.2 Portland blast furnace slag cement only;5.1.4.3 Slag-modified Portland cement only;5.1.4.4 Portland-pozzolan cement only;5.1.4.5 A combination of Portland cement and fly ash;5.1.4.6 A
19、combination of Portland cement and groundgranulated blast-furnace slag;5.1.4.7 A combination of Portland cement, ground granu-lated blast-furnace slag (not to exceed 25 %of the total cemen-titious weight), and fly ash (not to exceed 25 % of the totalcemenetitious weight).5.2 AggregatesAggregate shal
20、l conform to SpecificationC33 and light-weight aggregate shall conform to SpecificationC330, except that the requirements for grading shall not apply.5.3 AdmixturesAdmixtures may be used provided suchadmixtures are not injurious to other products used in theconcrete.5.3.1 Chemical AdmixturesChemical
21、 admixtures shallconform to Specification C494/C494M.5.3.2 Fly Ash and Pozzolanic AdmixtureFly ash or otherpozzolanic admixtures shall conform to Specification C618.5.3.3 Air-Entraining AdmixturesAir-entraining admix-tures shall conform to Specification C260.5.4 WaterWater used for curing, washing a
22、ggregate, ormixing concrete shall be clean and free of injurious amounts ofoil, acids, alkalis, salts, organic materials, or other substancesthat may be incompatible with concrete or steel.5.5 Steel Reinforcement:5.5.1 Wire ReinforcementWire reinforcement shall con-form to Specifications A82/A82M or
23、 A496/A496M.5.5.2 Wire Fabric ReinforcementWire fabric reinforce-ment shall conform to Specifications A185/A185M or A497/A497M.5.5.3 Bar ReinforcementBar reinforcement shall conformto Specifications A184/A184M, A615/A615M, A706/A706M,or A996/A996M.6. Manufacture6.1 FormsForms shall be accurately con
24、structed andstrong enough to maintain the structures dimensions withinthe tolerances given in Section 8. Forms should be constructedin such a manner as to minimize the seepage of water. Allcasting surfaces shall be smooth nonporous material.6.1.1 Cleaning and OilingForms shall be cleaned beforeeach
25、use. New forms shall be free of paint or other protectivecoatings that might cling to the surface of the structure.Releasing agents applied to the form to aid in breaking thebond between the form and the concrete shall not be injuriousto the concrete.6.2 ReinforcementSteel reinforcement shall confor
26、m tothe requirements of this specification and shall be securelypositioned in the form to maintain design concrete cover givenin Section 7 during concrete placement. All chairs, bolsters,braces, and spacers in contact with form and reinforcing rodshall be of material that will not deteriorate.6.3 Mi
27、xtureThe aggregates shall be sized, graded, propor-tioned, and thoroughly mixed in a batch mixer with proportionsof cement and water as will produce a homogeneous concretehaving the required specified compressive strength. If Ready-Mix concrete is used, it shall be in accordance with Specifica-tion
28、C94/C94M.6.3.1 Water-Cementitious Material RatioConcrete thatwill be exposed to freezing and thawing shall have a water-cementitious ratio of 0.45 or less.6.3.2 Air EntrainmentWhen there is a risk that the con-crete may be exposed to a freeze-thaw cycle, the concretemixture shall contain 5.5 6 1.5 %
29、 air by volume as determinedby Specification C231.6.4 Concrete PlacementConcrete shall be deposited asnearly as practicable in its final position. Concrete shall beplaced in the form at a rate such that the concrete is plastic atall times and flows readily into all parts of the form and aroundall re
30、inforcement steel and embedded fixtures without segre-gation of materials. Concrete that has partially hardened or hasbeen contaminated by foreign material shall not be deposited inthe form.6.5 CuringStructures shall be cured by an accepted in-dustry method that will develop the required 28-day comp
31、res-sive strength without affecting the long-term durability of theconcrete.7. Design Requirements7.1 The elastic method of structural design or the strengthdesign method of reinforced concrete design as outlined inACI 318, shall be used to design the concrete sections, includ-ing the reinforcement
32、required, when the structure is subjectedto the loading conditions covered in Practice C857.7.2 Access OpeningsThe structural design shall take intoconsideration the number, placement, and size of accessopenings.7.3 FloorsThe minimum floor thickness resulting fromslope shall be considered as the nom
33、inal floor thickness in thedesign of the structure.7.4 Terminators, Knockouts, and SumpsDuct terminators,knockouts, and sumps shall be designed to carry the loadsC858 1012imposed upon them. The basic structure shall be designed tocarry all imposed loads with knockouts removed.7.5 Placement of Reinfo
34、rcementThe design concretecover for reinforcing bars, mats, or fabric shall be not less than34 in. (19 mm) subject to the requirements of Section 8.7.6 Concrete StrengthThe minimum specified compres-sive strength for design shall be 3000 psi (21 MPa) at 28 daysof age. Compressive-strength tests shou
35、ld be made in accor-dance with Practices C31/C31M and C192/C192M and TestMethods C39/C39M and C42/C42M.7.7 JointsJoints in sectional precast concrete structureshall be designed so as to be self-aligning when assemblingsections of the structure.7.7.1 The manufacturer shall provide a single joint desi
36、gnon all units of the same size and type to ensure interchange-ability.7.8 Lifting DevicesDesign of lifting devices shall con-form to requirements as specified in the Lifting DevicesSection of Practice C857.8. Permissible Variations8.1 Dimensional TolerancesThe length, width, height, ordiameter meas
37、urements of the structure when measured on theinside surfaces shall not deviate from design dimensions bymore than the following:Dimensions Tolerance0to5ft(0to1.52m) 614 in. (66 mm)5 to 10 ft (1.52 to 3.05 m) 638 in. (610 mm)10 to 20 ft (3.058 to 6.10 m) 612 in. (613 mm)20 ft (6.10 m) and over as ag
38、reed upon between thesupplier and purchaser8.2 Squareness ToleranceThe inside of the precast con-crete component shall be square as determined by diagonalmeasurements. The difference between such measurementsshall not exceed the following:Measured Length Allowable Difference0to10ft(0to3.05m)12 in. (
39、13 mm)10 to 20 ft (3.05 to 6.10 m)34 in. (19 mm)20 ft (6.10 m) and over as agreed upon between thesupplier and purchaser8.3 Joint SurfacesThe inside joint seam gap between twosections placed together without a joint sealant shall not exceed38 in. (9.5 mm).8.4 Insert LocationInsert locations for atta
40、chments ineach component shall not deviate individually or cumulativelymore than 618 in. (3.18 mm) from dimensions on specificationdrawings.8.5 Reinforcement LocationWith reference to thicknessdimension of wall or slab, reinforcement shall be within 614in. (6.3 mm) of the design location but in no c
41、ase shall thecover be less than34 in. (19 mm). The reinforcement spacingshall not vary more than one tenth of the designed bar spacingnor exceed 112 in. (38 mm) in variation, except for welded wiremesh which shall conform to Specifications A185/A185M orA497/A497M.8.6 Slab and Wall ThicknessThe slab
42、and wall thicknessshall not be less than that shown in the design by more than5% or316 in. (4.8 mm), whichever is greater. A thicknessgreater than that required in the design shall not be a cause forrejection.9. Repairs9.1 Precast concrete structures may be repaired. Repairsshall be performed at the
43、 direction of the manufacturer in amanner to ensure that the repaired structure conforms to therequirements of this specification.10. Inspection10.1 The quality of materials, process of manufacture, andthe finished structure shall be subject to inspection at anytimeby the purchaser or his representa
44、tive.11. Rejection11.1 Precast concrete structures or sections of structuresshall be subject to rejection upon failure to conform to any ofthe specified requirements contained herein, or if any of thefollowing imperfections occur:11.1.1 Defects that indicate any imperfect concrete mixingand molding,
45、 or11.1.2 Surface defects indicated by honeycombed or open-texture and damaged areas where such defects would affect thestructural adequacy.12. Certification12.1 At the request of the purchaser, the manufacturer shall,prior to the actual delivery of a structure, furnish a statementgiving the source
46、and type of cement, the source and specificgravities of the aggregates, the concrete mix proportions,strength, type, amount, and name of admixtures and millcertificates for the reinforcement steel used in manufacture.13. Product Marking13.1 The weight shall be marked on the outside of eachcomponent
47、section.13.2 The purchaser may in his order request additionalinformation to be marked on the component section.13.3 The method of marking shall be agreed upon betweenthe purchaser and the supplier prior to ordering.concrete; manufacture; precast; structures; utilityC858 1013ASTM International takes
48、 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 of such rights, are entirely their own resp
49、onsibility.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 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 sho
