1、Designation: C1776/C1776M 17Standard Specification forWet-Cast Precast Modular Retaining Wall Units1This standard is issued under the fixed designation C1776/C1776M; the number immediately following the designation indicates theyear of original adoption or, in the case of revision, the year of last
2、revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers wet-cast precast modular re-taining wall units cast from first-purpose concrete with orwithout th
3、e inclusion of steel reinforcement. The precast unitscovered by this specification are machine-placed units intendedfor use in the construction of dry stacked modular retainingwall systems.1.2 The text of this standard references notes and footnotesthat provide explanatory material. These notes and
4、footnotes(excluding those in tables and figures) shall not be consideredas requirements of the standard.1.3 UnitsThe values stated in either inch-pound units orSI units are to be regarded separately as standard. Within thetext of the specification, the SI units are shown in brackets. Thevalues state
5、d in each system are not exact equivalents.Therefore, each system shall be used independently of theother. Combining values from the two systems may result innon-conformance with the standard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It
6、 is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2A615/A615M Specification for Deformed and Plain Carbon-Steel Bars for Concrete R
7、einforcementA706/A706M Specification for Deformed and Plain Low-Alloy Steel Bars for Concrete ReinforcementA767/A767M Specification for Zinc-Coated (Galvanized)Steel Bars for Concrete ReinforcementA775/A775M Specification for Epoxy-Coated Steel Rein-forcing BarsA884/A884M Specification for Epoxy-Coa
8、ted Steel Wireand Welded Wire ReinforcementA934/A934M Specification for Epoxy-Coated PrefabricatedSteel Reinforcing BarsA1055/A1055M Specification for Zinc and Epoxy DualCoated Steel Reinforcing BarsA1060/A1060M Specification for Zinc-Coated (Galvanized)Steel Welded Wire Reinforcement, Plain and Def
9、ormed,for ConcreteA1064/A1064M Specification for Carbon-Steel Wire andWelded Wire Reinforcement, Plain and Deformed, forConcreteC31/C31M Practice for Making and Curing Concrete TestSpecimens in the FieldC33/C33M Specification for Concrete AggregatesC39/C39M Test Method for Compressive Strength of Cy
10、lin-drical Concrete SpecimensC94/C94M Specification for Ready-Mixed ConcreteC125 Terminology Relating to Concrete and Concrete Ag-gregatesC138/C138M Test Method for Density (Unit Weight), Yield,and Air Content (Gravimetric) of ConcreteC143/C143M Test Method for Slump of Hydraulic-CementConcreteC150/
11、C150M Specification for Portland CementC173/C173M Test Method forAir Content of Freshly MixedConcrete by the Volumetric MethodC192/C192M Practice for Making and Curing Concrete TestSpecimens in the LaboratoryC231/C231M Test Method forAir Content of Freshly MixedConcrete by the Pressure MethodC260/C2
12、60M Specification for Air-Entraining Admixturesfor ConcreteC494/C494M Specification for Chemical Admixtures forConcreteC595/C595M Specification for Blended Hydraulic CementsC618 Specification for Coal Fly Ash and Raw or CalcinedNatural Pozzolan for Use in ConcreteC666/C666M Test Method for Resistanc
13、e of Concrete toRapid Freezing and ThawingC823/C823M Practice for Examination and Sampling ofHardened Concrete in ConstructionsC979/C979M Specification for Pigments for Integrally Col-ored Concrete1This test method is under the jurisdiction of ASTM Committee C27 on PrecastConcrete Products and is th
14、e direct responsibility of Subcommittee C27.20 onArchitectural and Structural Products.Current edition approved Feb. 1, 2017. Published February 2017. DOI: 10.1520/C1776_C1776M-17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org
15、. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with interna
16、tionally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1C989/C989M Specification for Slag Cement for Use i
17、nConcrete and MortarsC1157/C1157M Performance Specification for HydraulicCementC1611/C1611M Test Method for Slump Flow of Self-Consolidating Concrete2.2 ACI Documents:3ACI 318 Building Code Requirements for Structural Con-crete and Commentary3. Terminology3.1 DefinitionsTerminology defined in Termin
18、ology C125shall apply for this specification.3.2 Definitions:3.2.1 concrete, first-purpose, nhydraulic cement concreteprepared and used for its original intended purpose.3.2.2 width, unit, nregarding precast modular retainingwall unit dimensions, the term “width” shall refer to thehorizontal dimensi
19、on of the unit measured perpendicular to theface of the wall, from the front face of the unit to the back ofthe unit.3.2.3 height, unit, nregarding precast modular retainingwall unit dimensions, the term “height” shall refer to thevertical dimension of the unit as placed in the wall.3.2.4 length, un
20、it, nregarding precast modular retainingwall unit dimensions, the term “length” shall refer to thehorizontal dimension of the unit measured parallel to therunning length of the wall face.3.2.5 precast modular retaining wall unit, na machine-placed, solid, slotted or hollow, closed-cell, manufactured
21、concrete unit with nominal base length and nominal base widthdimensions greater than its vertical height as installed, used inthe construction of dry-stacked earth retaining walls.3.2.6 precast modular retaining wall unit, wet-cast, naprecast modular retaining wall unit, manufactured from con-crete
22、using a wet-cast process.3.2.7 wet cast, adjmanufactured concrete products madefrom fresh concrete with a measurable slump in accordancewith Test Method C143/C143M or slump flow in accordancewith Test Method C1611/C1611M.4. Ordering Information4.1 In the absence of designated applicable generalspeci
23、fications, the purchaser shall specify the following:4.1.1 Unit type and size with applicable dimensions.4.1.2 Compressive strength of the concrete used in themanufacture of the precast modular retaining wall units (see6.1).4.1.3 Air content of the concrete used in the manufacture ofthe precast modu
24、lar retaining wall units (see 6.2).4.1.4 Surface texture, finish and color of the precast modu-lar retaining wall units (see 8.5).4.1.5 Other special or custom features.4.1.6 Certification requirements (see 15.1).4.1.7 Protective coatings for reinforcing steel, if required(see 5.5.1 and 5.5.2).5. Ma
25、terials and Manufacture5.1 First-purpose concrete used for the production of precastmodular retaining wall units under this specification shall beready-mixed or central-mixed concrete conforming with Speci-fication C94/C94M.5.2 Cementitious materials shall conform to the followingapplicable specific
26、ations:5.2.1 Portland CementsSpecification C150/C150M.5.2.2 Blended Hydraulic CementsSpecification C595/C595M.5.2.3 Hydraulic CementSpecification C1157/C1157M.5.2.4 PozzolansSpecification C618.5.2.5 Slag CementSpecification C989/C989M.5.3 AggregatesAggregates shall conform to the followingspecificat
27、ions, except that grading requirements shall notnecessarily apply:5.3.1 Normal Weight AggregatesSpecification C33/C33M.5.4 AdmixturesSpecification C260/C260M, C494/C494M,orC979/C979M.5.5 Steel ReinforcementDesign, size, configuration, andplacement tolerance of reinforcing steel in any given precastm
28、odular retaining wall unit is proprietary and shall be deter-mined by the manufacturer based upon the structural require-ments of the units produced. The proprietary reinforcementdesign of the precast modular retaining wall unit(s) shall beprepared and sealed by a licensed professional engineer.Rein
29、forcing steel placed within precast modular retaining wallunits for the purpose of resisting loading stress shall conformwith the following:5.5.1 Reinforcing BarsSteel reinforcing bars used as rein-forcement in precast modular retaining wall units shall exhibita minimum yield stress of 60 ksi 420 MP
30、a. Deformed or plainbars shall meet the requirements of Specification A615/A615M. Reinforcing bars that are welded shall meet therequirements of Specification A706/A706M. Zinc-coated (gal-vanized) steel reinforcing bars shall meet the requirements ofSpecification A767/A767M. Epoxy-coated steel reinf
31、orcingbars shall meet the requirements of Specification A775/A775M, A934/A934M,orA1055/A1055M as required by thepurchaser.5.5.2 Welded Wire Reinforcement (WWR)Steel weldedwire reinforcement (WWR) used in welded reinforcement matsin precast modular retaining wall units shall exhibit a minimumyield st
32、ress of 65 ksi 450 MPa. Deformed or plain WWRshall meet the requirements of Specification A1064/A1064M.Zinc-coated (galvanized) WWR shall meet the requirements ofSpecification A1060/A1060M. Epoxy-coated WWR shall meetthe requirements of Specification A884/A884M.5.6 Lifting DevicesLifting device(s) f
33、or use in final place-ment of the precast modular retaining wall unit shall meetOSHA requirements documented in “Code of Federal Regula-tions” Title 29 Part 1926. Manufacturers of lifting devices shall3Available from American Concrete Institute (ACI), 38800 Country Club Dr.,Farmington Hills, MI 4833
34、1-3439, http:/www.concrete.org.C1776/C1776M 172report test data demonstrating the load capacity of the liftingdevice. Manufacturers of embedded lifting devices shall dem-onstrate the suitability of protective coatings or added sacrifi-cial section thickness of the lifting device for use in highmoist
35、ure or other corrosive environments as appropriate to theend use of the precast modular retaining wall unit.5.7 Other ConstituentsPost-production applied colorstains, integral water repellents, finely ground silica, reinforc-ing fibers, and other constituents shall be previously estab-lished as suit
36、able for use in precast modular retaining wall unitsand shall conform to applicable ASTM standards.6. Physical Properties6.1 Compressive StrengthConcrete used in the manufac-ture of the precast modular retaining wall units shall exhibit aminimum compressive strength of 4,000 psi 28 MPa whentested in
37、 accordance with Test Method C39/C39M at 28 days.Units with a higher compressive strength shall be providedwhen required by the purchase order or contract.6.2 Air ContentIn project locations where repeated freez-ing and thawing under saturated conditions may occur, aircontent for the concrete mix sh
38、all be provided in accordancewith the anticipated exposure condition as defined in Specifi-cation C94/C94M. Other air content for the concrete mix shallbe provided when required by the purchase order or contract.7. Dimensions, Mass, and Permissible Variations7.1 Overall dimensions for height shall d
39、iffer by not morethan 6316 in. 5 mm, and length shall differ by not more than612 in. 13 mm from the specified standard dimensions.7.2 Overall dimension for width shall not be more than12in. 13 mm less than the specified standard width. Dimen-sional tolerance requirements for width shall be waived fo
40、rarchitectural surfaces.7.3 For precast modular retaining wall units with a rectan-gular exposed face, the diagonal dimensions of the exposedface shall not differ by more than12 in. 13 mm. Measurementof the diagonal dimensions of the exposed face shall beexclusive of the architectural face texture.7
41、.4 Minimum concrete cover over all steel reinforcementtypes specified in 5.5 shall be 1 in. 25 mm except where asurface is to be exposed to an aggressive environment such asdeicing chemicals or brackish water. Surfaces exposed to anaggressive environment shall provide minimum cover to steelreinforce
42、ment of 2 in. 51 mm.7.5 Precast modular retaining wall units produced with steelreinforcement protruding beyond the manufactured dimensionsof the unit for the purpose of connection to adjacent cast-in-place concrete structures shall be allowed under this specifi-cation. The minimum cover requirement
43、s in 7.4 are waived forthe portion of the steel reinforcement that extends beyond theprecast modular retaining wall unit.8. Workmanship, Finish, and Appearance8.1 Individual precast modular retaining wall units shall notbe removed from the form cell until the unit has reached asufficient compressive
44、 strength that will permit the extractionto occur without resulting in damage to the unit. The minimumpermissible compressive strength of the precast modular re-taining wall unit prior to removal from the form cell shall beestablished by the manufacturer before the units are cast.8.2 Test cylinders
45、prepared from concrete used in theproduction of the precast modular retaining wall units shalldemonstrate 100 % of the required minimum 28-day compres-sive strength prior to shipment or installation of the units.8.3 All precast modular retaining wall units shall be soundand free of cracks or other d
46、efects that interfere with the properplacement of the unit.8.4 Upon delivery to the purchaser, precast modular retain-ing wall units to be used in exposed wall construction shall notexhibit chips or cracks in the exposed face or faces of the unitthat are not otherwise permitted as follows:8.4.1 Chip
47、s smaller than 1.5 in. 38 mm in its largestdimension and cracks not wider than 0.012 in. 0.3 mm andnot longer than 25 % of the nominal height of the precastmodular retaining wall unit shall be permitted. Likewise, othervoids or inconsistencies in the exposed architectural face of theunit smaller tha
48、n 0.75 in. 19 mm in its largest dimension shallbe permitted.8.4.2 Cracks that are continuous through any solid elementof the precast modular retaining wall unit shall be grounds forrejection of the unit regardless of the width or length of thecrack.8.5 The color and texture of the precast modular re
49、tainingwall units shall be selected from the range of colors andtextures available from the manufacturer. The finished surfacethat will be exposed in the final construction shall conform toan approved sample consisting of not less than four (4) unitsrepresenting the range of texture and color selected by thepurchaser.NOTE 1Wet-cast, precast modular retaining walls consist of manyindividual precast modular retaining wall units that are often manufac-tured with purposeful variations of complementary and/or contrastingtextures, colors
