1、Designation: C1623 11Standard Specification forManufactured Concrete Masonry Lintels1This standard is issued under the fixed designation C1623; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in
2、parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers concrete masonry lintels(beams) that are solid in cross-section, are reinforced forflexure, and are made from hydrauli
3、c cement, water, andmineral aggregates with or without the inclusion of othermaterials. These lintels are suitable for both loadbearing andnonloadbearing applications.NOTE 1This specification covers only concrete masonry lintels con-taining reinforcement. Due to building code imposed limitations on
4、thedesign of masonry lintels, all lintels must contain reinforcement. Concretemasonry lintels are not typically manufactured using shear reinforcement(stirrups or other vertical reinforcement). Therefore, this standard does notaddress issues related to such. For further guidance, refer to Building C
5、odeRequirements for Masonry Structures, TMS 402/ACI 530/ASCE 5. Pre-stressed concrete lintels are not covered by this standard.1.2 Lintels are manufactured using a no-slump concrete mixto provide a surface texture similar to that of concrete masonry.This specification applies to both machine-made an
6、d hand-tamped concrete masonry lintels intended for use in concretemasonry applications.1.3 Concrete masonry lintels covered by this specificationare made from lightweight or normal weight aggregates, orboth.1.4 This specification does not address the design or analy-sis of lintel capacity. Structur
7、al evaluations must be performedseparately. The strength of a lintel is a function of factorsincluding, but not limited to, the characteristics of the materialsused in manufacturing (concrete materials and reinforcement),the amount and location of reinforcement, and the manufac-turing and curing pro
8、cedures. For design and analysis methods,refer to Building Code Requirements for Masonry Structures,TMS 402/ACI 530/ASCE 5.1.5 This specification does not cover U-shaped lintels orthose of other cross-sections that are not 100 % solid.1.6 This specification does not cover lintels of groutedconcrete
9、masonry lintels, or precast or cast-in-place lintels ofslump concrete.1.7 The text of this standard references notes and footnotesthat provide explanatory material. These notes and footnotes(excluding those in tables and figures) shall not be consideredas requirements of the standard.1.8 The values
10、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:2A615/A615M Specification for Deformed and PlainCarbon-Ste
11、el Bars for Concrete ReinforcementA706/A706M Specification for Low-Alloy Steel Deformedand Plain Bars for Concrete ReinforcementA996/A996M Specification for Rail-Steel and Axle-SteelDeformed Bars for Concrete ReinforcementC33 Specification for Concrete AggregatesC140 Test Methods for Sampling and Te
12、sting ConcreteMasonry Units and Related UnitsC150 Specification for Portland CementC331 Specification for Lightweight Aggregates for Con-crete Masonry UnitsC595 Specification for Blended Hydraulic CementsC618 Specification for Coal Fly Ash and Raw or CalcinedNatural Pozzolan for Use in ConcreteC979
13、Specification for Pigments for Integrally ColoredConcreteC989 Specification for Slag Cement for Use in Concreteand MortarsC1157 Performance Specification for Hydraulic CementC1232 Terminology of MasonryC1240 Specification for Silica Fume Used in CementitiousMixturesC1262 Test Method for Evaluating t
14、he Freeze-Thaw Dura-bility of Dry-Cast Segmental Retaining Wall Units andRelated Concrete Units2.2 Other StandardsTMS 402/ACI 530/ASCE 5 Building Code Requirements1This specification is under the jurisdiction of ASTM Committee C15 onManufactured Masonry Units and is the direct responsibility of Subc
15、ommitteeC15.03 on Concrete Masonry Units and Related Units.Current edition approved Dec. 15, 2011. Published January 2012. Originallyapproved in 2005. Last previous edition approved in 2006 as C1623 06. DOI:10.1520/C1623-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcont
16、act ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West
17、 Conshohocken, PA 19428-2959, United States.for Masonry StructuresTMS 602/ACI 530.1/ASCE 6 Specification for MasonryStructures3. Terminology3.1 Terminology defined in Terminology C1232 shall applyfor this specification.4. Material4.1 Cementitious MaterialsMaterials shall conform to thefollowing appl
18、icable specifications: 4.1.1 Portland CementSpecification C150.4.1.1 Portland CementSpecification C150.4.1.2 Modified Portland CementPortland cement con-forming to Specification C150, modified as follows:(1) Limestone If calcium carbonate is added to the cement,the CaCO3content shall be not less tha
19、n 85 %.(2) Limitation on Insoluble Residue1.5 %.(3) Limitation on Air Content of MortarVolume percent,22 % max.(4) Limitation on Loss on Ignition7 %.4.1.3 Blended Hydraulic CementsSpecification C5954.1.4 Hydraulic Cement Specification C1157.4.1.5 PozzolansSpecification C618.4.1.6 Ground Granulated B
20、last Furnace SlagSpecification C989.4.1.7 Silica FumeSpecification C1240.4.2 AggregatesAggregates shall conform to the follow-ing specifications, except that grading requirements shall notnecessarily apply:4.2.1 Normal Weight AggregatesSpecification C33.4.2.2 Lightweight AggregatesSpecification C331
21、.4.3 Pigments for Integrally Colored ConcreteSpecification C979.4.4 Steel ReinforcementSteel reinforcement shall consistof deformed bars conforming to Specifications A615/A615M,A706/A706M,orA996/A996M.4.5 Other ConstituentsAir-entraining agents, integralwater repellents, and other constituents shall
22、 be previouslyestablished as suitable for use in concrete masonry lintels andshall conform to applicable ASTM standards or shall be shownby test or experience not to be detrimental to the durability ofthe concrete masonry lintels or any material customarily usedin masonry construction.5. Physical Re
23、quirements5.1 At the time of delivery to the purchaser, the concretewithin the lintel shall conform to the requirements prescribedin Table 1.5.1.1 When higher compressive strengths than those listedin Table 1 are specified, the tested average net area compres-sive strength of three specimens shall e
24、qual or exceed thespecified compressive strength, and the tested individual speci-men net area compressive strength of all three units shallexceed 90 % of the specified compressive strength.NOTE 2When particular features are desired such as surface texturesfor appearance or bond, finish, color, or p
25、articular properties such asspecific reinforcing schedules, flexural strength, weight per unit length,higher compressive strength, or fire resistance, these features are specifiedseparately by the purchaser. Consult suppliers as to the availability oflintels having the desired features.5.2 All linte
26、ls shall be sound and free of cracks or otherdefects that interfere with proper placement unless defects areconsidered to be not detrimental to structural capacity of thelintel before or after defects are repaired using practicessatisfactory to the engineer.NOTE 3The purchaser is the public body or
27、authority, association,corporation, partnership, or individual entering into a contract or agree-ment to purchase or install, or both, concrete masonry lintels. The time ofdelivery to the purchaser is FOB plant when the purchaser or thepurchasers agent transports the concrete masonry lintels, or at
28、the timeunloaded at the worksite if the manufacturer or the manufacturers agenttransports the concrete masonry lintels.NOTE 4When these lintels are used in above-grade applications aspart of a vertical, free-draining assemblage, the physical requirements inthis specification have been shown to resul
29、t in durable products. Inapplications where the lintels are frequently exposed to deicing chemicalsor saturated conditions in conjunction with freezing and thawing tempera-tures, testing should be considered to evaluate freezing and thawingresistance using ASTM C1262.6. Permissible Variations in Dim
30、ensions6.1 Overall dimensions for width, and height shall differ bynot more than 618 in. (3.2 mm) from the specified standarddimensions. Overall dimension for length shall differ by notmore than 0.5 % from the specified length.6.2 Warpage6.2.1 The longitudinal straightness of each of the four facess
31、hall not deviate from a straight line more than14 in. (6 mm)over 10 ft (3.05 m). Measure deviations with lintel resting onflat, horizontal surface.TABLE 1 Strength, Absorption, and Density Classification RequirementsADensity Classification Oven-Dry Densityof Concrete, lb/ft3(kg/m3)Maximum WaterAbsor
32、ption, lb/ft3(kg/m3)Minimum Net AreaCompressive Strength,psi (MPa)Average of3 SpecimensBAverage of3 SpecimensBIndividualSpecimenBAverage of3 SpecimensBIndividualSpecimenBLightweight Less than105 (1680) 18 (288) 20 (320) 2500 (17.2) 2250 (15.5)Medium Weight 105 to less than 125 (16802000) 15 (240) 17
33、 (272) 2500 (17.2) 2250 (15.5)Normal Weight 125 (2000) or more 13 (208) 15 (240) 2500 (17.2) 2250 (15.5)AConsult manufacturers for available densities.BRefer to section 9.2.1 for specimen requirements.C1623 1126.2.2 The cross-section of the lintel shall not deviate fromsquare more than18 in. (3 mm)
34、over 8 in. (203 mm) in height.7. Requirements for Reinforcement7.1 Reinforcement and its placement shall comply withBuilding Code Requirements for Masonry Structures,TMS 402/ACI 530/ASCE 5 and Specification for MasonryStructures, TMS 602/ACI 530.1/ASCE 6 with the followingexceptions.7.1.1 Specified
35、vertical depth of longitudinal reinforcementshall be equal to or greater than the specified depth minus 0.5in. (12.7 mm) (Fig. 1a).7.1.2 When a single longitudinal reinforcing bar is used at agiven depth, the specified horizontal depth of that reinforce-ment shall be 61 in. (25.4 in.) from the speci
36、fied depth (Fig.1b).7.1.3 When multiple longitudinal reinforcing bars are usedat a given depth, the specified horizontal depth of each bar shallbe equal to or greater than the specified depth minus 0.5 in.(12.7 mm) (Fig. 1c).7.2 Splicing of reinforcing bars is not permitted.7.3 End of reinforcing ba
37、rs shall be terminated not less than1.5 in. (38 mm) and not more than 3 in. (76 mm) from the endof the lintel. These requirements do not apply to non-structuralreinforcing bars (i.e. those used to facilitate handling andtransportation) nor to those reinforcing bars manufactured toextend past the end
38、 of the lintel.NOTE 5Lintels are sometimes manufactured with reinforcing barsextending past the end of the lintel. Consult applicable codes to determineif such bars need to be embedded in grout or otherwise connected to thestructure or protected.7.4 Manufacturer shall maintain records of mill certif
39、ica-tions for reinforcement and shall make such records availableon request by the purchaser.8. Finish and Appearance8.1 Where lintels are to be used in exposed wall construc-tion, the face or faces that are to be exposed shall not showchips or cracks, not otherwise permitted, or other imperfections
40、when viewed from a distance of not less than 20 ft (6.1 m)under diffused lighting.8.2 The purchaser shall specify the color and texture oflintels. The finished surfaces that will be exposed in place shallconform to an approved sample consisting of not less than fourlintels, representing the range of
41、 texture and color permitted onthe project.9. Sampling and Testing9.1 The purchaser or authorized representative shall beaccorded proper facilities to inspect and sample the lintels atthe place of manufacture from the lots ready for delivery.9.2 Sample and test lintels for compression and absorption
42、in accordance with Test Methods C140 with the followingdeviations.9.2.1 Compression tests shall be performed on three speci-mens, each measuring nominally 4 in. (100 mm) in width, 8 in.(200 mm) in length and 8 in. (200 mm) in height. The aspectratio of each test specimen (measured height divided bym
43、easured width) shall by 2.0 6 0.1. The height of the specimenshall be in the same orientation as the height of the lintel. Onespecimen shall be saw-cut from each of three lintels with orwithout horizontal reinforcing bars within the specimen.NOTE 6Because concrete masonry lintels contain reinforcing
44、 steel itis often impractical to obtain compression specimens that do not containreinforcement. Saw-cuts that are made perpendicular to the length of thereinforcement do not typically damage the integrity of the compressionspecimen being removed if the blade is sharp and in good working order.Horizo
45、ntal reinforcing bars that are oriented perpendicular to the directionFIG. 1 Cross Section of Concrete Masonry LintelC1623 113of compression loading do not significantly affect the tested strength of thespecimen.9.2.2 Absorption tests shall be performed on three speci-mens, each having greater than
46、200 in3(3280 cm3) in volume.One specimen shall be saw-cut from each of three lintels. Thespecimen shall be cut such that it does not contain reinforcingbars.NOTE 7A specimen measuring nominally 4 in. (100 mm) in width, 8in. (200 mm) in length and 8 in. (200 mm) in height is typically easy toobtain a
47、nd meets the volume requirements for absorption specimens.9.2.3 When saw-cutting of compression and absorptionspecimens exposes reinforcement, document and report thefollowing:9.2.3.1 Number of bars and a sketch or description of theirlocation.9.2.3.2 Size (diameter) of each bar.9.2.3.3 Vertical loc
48、ation of each bar, measured from top oflintel to center of bar, in. (mm)9.2.3.4 Horizontal location of each bar, measured from eachface of the lintel to the center of bar, in. (mm)10. Compliance10.1 If a sample fails to conform to the specified require-ments, the manufacturer shall be permitted to r
49、emove lintelsfrom the shipment. A new sample shall be selected by thepurchaser from remaining lintels from the shipment with asimilar configuration and dimension and tested at the expenseof the manufacturer. If the second sample meets the specifiedrequirements, the remaining portion of the shipment repre-sented by the sample meets the specified requirements. If thesecond sample fails to meet the specified requirements, theremaining portion of the shipment represented by the samplefails to meet the specified requirements.NOTE 8Unless otherwise spec
