1、Designation: C858 101C858 18Standard 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 revisi
2、on. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1 NOTEAir entrainment admixture information was moved editorially from subsection 5.3.3 to subsection 6.3.2 inNovember 2010.1. Scope1.1 This
3、specification covers the recommended design criteria and manufacturing practices for monolithic or sectional precastconcrete utility structures. Concrete pipe and box culverts are not covered under this specification.Also, precast concrete manholescovered in Specification C478 are excluded from this
4、 specification.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information only and are not considered standard.1.3 This international standard was developed in accordance with int
5、ernationally 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.2. Referenced Documents2.1 ASTM Standards:2A82/A
6、82M Specification for Steel Wire, Plain, for Concrete Reinforcement (Withdrawn 2013)3A184/A184M Specification for Welded Deformed Steel Bar Mats for Concrete ReinforcementA185/A185M Specification for Steel Welded Wire Reinforcement, Plain, for Concrete (Withdrawn 2013)3A496/A496M Specification for S
7、teel Wire, Deformed, for Concrete Reinforcement (Withdrawn 2013)3A497/A497M Specification for Steel Welded Wire Reinforcement, Deformed, for Concrete (Withdrawn 2013)3A615/A615M Specification for Deformed and Plain Carbon-Steel Bars for Concrete ReinforcementA706/A706M Specification for Deformed and
8、 Plain Low-Alloy Steel Bars for Concrete ReinforcementA996/A996M Specification for Rail-Steel and Axle-Steel Deformed Bars for Concrete ReinforcementA1064/A1064M Specification for Carbon-Steel Wire and Welded Wire Reinforcement, Plain and Deformed, for ConcreteC31/C31M Practice for Making and Curing
9、 Concrete Test Specimens in the FieldC33 Specification for Concrete AggregatesC39/C39M Test Method for Compressive Strength of Cylindrical Concrete SpecimensC42/C42M Test Method for Obtaining and Testing Drilled Cores and Sawed Beams of ConcreteC94/C94M Specification for Ready-Mixed ConcreteC150 Spe
10、cification for Portland CementC192/C192M Practice for Making and Curing Concrete Test Specimens in the LaboratoryC231 Test Method for Air Content of Freshly Mixed Concrete by the Pressure MethodC260 Specification for Air-Entraining Admixtures for ConcreteC330 Specification for Lightweight Aggregates
11、 for Structural ConcreteC478 Specification for Circular Precast Reinforced Concrete Manhole SectionsC494/C494M Specification for Chemical Admixtures for ConcreteC595 Specification for Blended Hydraulic CementsC618 Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concret
12、e1 This specification is under the jurisdiction of ASTM Committee C27 on Precast Concrete Products and is the direct responsibility of Subcommittee C27.10 on UtilityStructures.Current edition approved Feb. 15, 2010Jan. 1, 2018. Published February 2010January 2018. Originally approved in 1978. Last p
13、revious edition approved in 20092010as C858 09.C858 101. DOI: 10.1520/C0858-10E01.10.1520/C0858-18.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Docu
14、ment Summary page on the ASTM website.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 all changes accurately, ASTM r
15、ecommends 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 19428-2959. United States1C857 Pract
16、ice for Minimum Structural Design Loading for Underground Precast Concrete Utility StructuresC989 Specification for Slag Cement for Use in Concrete and Mortars2.2 American Concrete Institute Standard:ACI 318 Building Code Requirements for Reinforced Concrete32.3 American Welding Society Standard:AWS
17、-D1.4 Structural Welding Code Reinforcing Steel43. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 utility structurea structure that is used by electric, gas, communication, or similar industries.4. Ordering Information4.1 Unless otherwise stipulated by the purchaser in his order
18、, a structure produced in accordance with this specification andconstructed in accordance with the design drawings approved by the purchaser shall be acceptable.5. Materials5.1 Cementitious Materials:5.1.1 CementCement shall conform to the requirements for Portland cement of Specification C150 or sh
19、all be Portlandblast-furnace slag cement or Portland-pozzolan cement conforming to the requirements of Specification C595, except that thepozzolan constituent in the Type IP Portland-pozzolan cement shall be fly ash.5.1.2 Fly AshFly ash shall conform to the requirements of Specification C618, Class
20、F or Class C.5.1.3 Ground Granulated Blast-Furnace Slag (GGBFS)GGBFS shall conform to the requirements of Grade 100 or 120 ofSpecification C989.5.1.4 Allowable Combinations of Cementitious MaterialThe combination of cementitious materials used in concrete shall beone of the following:5.1.4.1 Portlan
21、d 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 combination of Portland cement and ground granulated blast-furnace slag;5.1.4.7 A combination
22、of Portland cement, ground granulated blast-furnace slag (not to exceed 25 %of the total cementitiousweight), and fly ash (not to exceed 25 % of the total cemenetitious weight).5.2 AggregatesAggregate shall conform to Specification C33 and light-weight aggregate shall conform to Specification C330,e
23、xcept that the requirements for grading shall not apply.5.3 AdmixturesAdmixtures may be used provided such admixtures are not injurious to other products used in the concrete.5.3.1 Chemical AdmixturesChemical admixtures shall conform to Specification C494/C494M.5.3.2 Fly Ash and Pozzolanic Admixture
24、Fly ash or other pozzolanic admixtures shall conform to Specification C618.5.3.3 Air-Entraining AdmixturesAir-entraining admixtures shall conform to Specification C260.5.4 WaterWater used for curing, washing aggregate, or mixing concrete shall be clean and free of injurious amounts of oil,acids, alk
25、alis, salts, organic materials, or other substances that may be incompatible with concrete or steel.5.5 Steel Reinforcement:5.5.1 Wire ReinforcementWire reinforcement shall conform to Specifications A82/A82M or A496/A496M.5.5.1 Wire and Wire Fabric ReinforcementWire and wire fabric reinforcement sha
26、ll conform to SpecificationsSpecificationA185/A185MA1064/A1064M or A497/A497M.5.5.2 Bar ReinforcementBar reinforcement shall conform to Specifications A184/A184M, A615/A615M, A706/A706M, orA996/A996M.6. Manufacture6.1 FormsForms shall be accurately constructed and strong enough to maintain the struc
27、tures dimensions within thetolerances given in Section 8. Forms should be constructed in such a manner as to minimize the seepage of water. All castingsurfaces shall be smooth nonporous material.3 Available from American Concrete Institute (ACI), P.O. Box 9094, Farmington Hills, MI 48333-9094, http:
28、/www.aci-int.org.4 Available from American Welding Society (AWS), 550 NW LeJeune Rd., Miami, FL 33126, http:/www.aws.org.C858 1826.1.1 Cleaning and OilingForms shall be cleaned before each use. New forms shall be free of paint or other protectivecoatings that might cling to the surface of the struct
29、ure. Releasing agents applied to the form to aid in breaking the bond betweenthe form and the concrete shall not be injurious to the concrete.6.2 ReinforcementSteel reinforcement shall conform to the requirements of this specification and shall be securely positionedin the form to maintain design co
30、ncrete cover given in Section 7 during concrete placement.All chairs, bolsters, braces, and spacersin contact with form and reinforcing rod shall be of material that will not deteriorate.6.3 MixtureThe aggregates shall be sized, graded, proportioned, and thoroughly mixed in a batch mixer with propor
31、tions ofcement and water as will produce a homogeneous concrete having the required specified compressive strength. If Ready-Mixconcrete is used, it shall be in accordance with Specification C94/C94M.6.3.1 Water-Cementitious Material RatioConcrete that will be exposed to freezing and thawing shall h
32、ave a water-cementitious ratio of 0.45 or less.6.3.2 Air EntrainmentWhen there is a risk that the concrete may be exposed to a freeze-thaw cycle, the concrete mixture shallcontain 5.5 6 1.5 % air by volume as determined by Specification C231.6.4 Concrete PlacementConcrete shall be deposited as nearl
33、y as practicable in its final position. Concrete shall be placed inthe form at a rate such that the concrete is plastic at all times and flows readily into all parts of the form and around allreinforcement steel and embedded fixtures without segregation of materials. Concrete that has partially hard
34、ened or has beencontaminated by foreign material shall not be deposited in the form.6.5 CuringStructures shall be cured by an accepted industry method that will develop the required 28-day compressivestrength without affecting the long-term durability of the concrete.7. Design Requirements7.1 The el
35、astic method of structural design or the strength design method of reinforced concrete design as outlined in ACI 318,shall be used to design the concrete sections, including the reinforcement required, when the structure is subjected to the loadingconditions covered in Practice C857.7.2 Access Openi
36、ngsThe structural design shall take into consideration the number, placement, and size of access openings.7.3 FloorsThe minimum floor thickness resulting from slope shall be considered as the nominal floor thickness in the designof the structure.7.4 Terminators, Knockouts, and SumpsDuct terminators,
37、 knockouts, and sumps shall be designed to carry the loads imposedupon them. The basic structure shall be designed to carry all imposed loads with knockouts removed.7.5 Placement of ReinforcementThe design concrete cover for reinforcing bars, mats, or fabric shall be not less than 34 in.(19 mm) subj
38、ect to the requirements of Section 8.7.6 Concrete StrengthThe minimum specified compressive strength for design shall be 3000 psi (21 MPa) at 28 days of age.Compressive-strength tests should be made in accordance with Practices C31/C31M and C192/C192M and Test MethodsC39/C39M and C42/C42M.7.7 Joints
39、Joints in sectional precast concrete structure shall be designed so as to be self-aligning when assembling sectionsof the structure.7.7.1 The manufacturer shall provide a single joint design on all units of the same size and type to ensure interchangeability.7.8 Lifting DevicesDesign of lifting devi
40、ces shall conform to requirements as specified in the Lifting Devices Section ofPractice C857.8. Permissible Variations8.1 Dimensional TolerancesThe length, width, height, or diameter measurements of the structure when measured on the insidesurfaces shall not deviate from design dimensions by more t
41、han the following:Dimensions Tolerance0 to 5 ft (0 to 1.52 m) 14 in. (6 mm)5 to 10 ft (1.52 to 3.05 m) 38 in. (10 mm)10 to 20 ft (3.058 to 6.10 m) 12 in. (13 mm)20 ft (6.10 m) and over as agreed upon between thesupplier and purchaser8.2 Squareness ToleranceThe inside of the precast concrete componen
42、t shall be square as determined by diagonalmeasurements. The difference between such measurements shall not exceed the following:Measured Length Allowable Difference0 to 10 ft (0 to 3.05 m) 12 in. (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 thesup
43、plier and purchaserC858 1838.3 Joint SurfacesThe inside joint seam gap between two sections placed together without a joint sealant shall not exceed 38in. (9.5 mm).8.4 Insert LocationInsert locations for attachments in each component shall not deviate individually or cumulatively morethan 618 in. (3
44、.18 mm) from dimensions on specification drawings.8.5 Reinforcement LocationWith reference to thickness dimension of wall or slab, reinforcement shall be within 614 in. (6.3mm) of the design location but in no case shall the cover be less than 34 in. (19 mm). The reinforcement spacing shall not vary
45、more than one tenth of the designed bar spacing nor exceed 112 in. (38 mm) in variation, except for welded wire mesh which shallconform to SpecificationsSpecification A185/A185MA1064/A1064M or A497/A497M.8.6 Slab and Wall ThicknessThe slab and wall thickness shall not be less than that shown in the
46、design by more than 5 % or316 in. (4.8 mm), whichever is greater. A thickness greater than that required in the design shall not be a cause for rejection.9. Repairs9.1 Precast concrete structures may be repaired. Repairs shall be performed at the direction of the manufacturer in a mannerto ensure th
47、at the repaired structure conforms to the requirements of this specification.10. Inspection10.1 The quality of materials, process of manufacture, and the finished structure shall be subject to inspection at anytime by thepurchaser or his representative.11. Rejection11.1 Precast concrete structures o
48、r sections of structures shall be subject to rejection upon failure to conform to any of thespecified requirements contained herein, or if any of the following imperfections occur:11.1.1 Defects that indicate any imperfect concrete mixing and molding, or11.1.2 Surface defects indicated by honeycombe
49、d 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 statement givingthe source and type of cement, the source and specific gravities of the aggregates, the concrete mix proportions, strength, type,amount, and name of admixtures and mill certificates for the reinforcement steel used in manufacture.13. Product Marking13.1 The weight shall be marked o
