1、Designation: C90 12Standard Specification forLoadbearing Concrete Masonry Units1This standard is issued under the fixed designation C90; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revision. A number in parenth
2、eses indicates the year of last reapproval. A superscriptepsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This specification covers hollow and solid (see 5.3 and5.4) concrete m
3、asonry units made from hydraulic cement,water, and mineral aggregates with or without the inclusion ofother materials. There are three classes of concrete masonryunits: (1) normal weight, (2) medium weight, and (3) light-weight. These units are suitable for both loadbearing andnonloadbearing applica
4、tions.1.2 Concrete masonry units covered by this specification aremade from lightweight or normal weight aggregates, or both.NOTE 1The requirements of this specification have been researched,evaluated, and established for over a century, resulting in the physicalproperties and attributes defined her
5、e. These requirements are uniquelyand solely applicable to concrete masonry units manufactured on equip-ment using low or zero slump concrete and the constituent materialsdefined herein. Many performance attributes of concrete masonry units areindirectly accounted for, or inherently reflected within
6、, the requirementsof this specification without direct measurement, assessment, or evalua-tion. Applying the requirements of this specification to products that maybe similar in appearance, use, or nature to those covered by thisspecification may not address all pertinent physical properties necessa
7、ry toensure performance or serviceability of the resulting construction inreal-world applications under typical exposure environments. Productsmanufactured using alternative materials, manufacturing methods, orcuring processes not covered by this specification should not be evaluatedsolely using the
8、 requirements in this specification, however, developers ofnew products can consider the property requirements of this specificationas a beginning benchmark for unit performance. It is reasonable to testnew products for system performance as well as unit performance.1.3 The text of this specificatio
9、n references notes andfootnotes which provide explanatory material. These notes andfootnotes (excluding those in tables and figures) shall not beconsidered as requirements of the standard.1.4 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mat
10、hematicalconversions to SI units that are provided for information onlyand are not considered standard.NOTE 2When particular features are desired such as surface texturesfor appearance or bond, finish, color, or particular properties such asdensity classification, higher compressive strength, fire r
11、esistance, thermalperformance or acoustical performance, these features should be specifiedseparately by the purchaser. Suppliers should be consulted as to theavailability of units having the desired features.2. Referenced Documents2.1 ASTM Standards:2C33 Specification for Concrete AggregatesC140 Te
12、st Methods for Sampling and Testing ConcreteMasonry Units and Related UnitsC150 Specification for Portland CementC331 Specification for Lightweight Aggregates for ConcreteMasonry UnitsC426 Test Method for Linear Drying Shrinkage of ConcreteMasonry UnitsC595 Specification for Blended Hydraulic Cement
13、sC618 Specification for Coal Fly Ash and Raw or CalcinedNatural Pozzolan for Use in ConcreteC979 Specification for Pigments for Integrally Colored Con-creteC989 Specification for Slag Cement for Use in Concrete andMortarsC1157 Performance Specification for Hydraulic CementC1232 Terminology of Masonr
14、yC1240 Specification for Silica Fume Used in CementitiousMixturesC1314 Test Method for Compressive Strength of MasonryPrismsE519 Test Method for Diagonal Tension (Shear) in MasonryAssemblagesE72 Test Methods of Conducting Strength Tests of Panelsfor Building Construction3. Terminology3.1 Terminology
15、 defined in Terminology C1232 shall applyfor this specification.1This specification is under the jurisdiction of ASTM Committee C15 onManufactured Masonry Units and is the direct responsibility of SubcommitteeC15.03 on Concrete Masonry Units and Related Units.Current edition approved Aug. 1, 2012. P
16、ublished August 2012. Originallyapproved in 1931. Last previous edition approved in 2011 as C90 11b. DOI:10.1520/C0090-12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, ref
17、er to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Materials4.1 Cementitious MaterialsMaterials shall confor
18、m to thefollowing applicable specifications:4.1.1 Portland CementSpecification C150.4.1.2 Modified Portland CementPortland cement con-forming to Specification C150, modified as follows:(1) LimestoneIf calcium carbonate is added to the ce-ment, the CaCO3content shall not be less than 85 %.(2) Limitat
19、ion 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 C595.4.1.4 Hydraulic CementSpecification C1157.4.1.5 PozzolansSpecification C618.4.1.6 Blast Furnace Slag CementSpecificatio
20、n C989.4.1.7 Silica FumeSpecification C1240.4.2 AggregatesAggregates shall conform to the followingspecifications, except that grading requirements shall notnecessarily apply:4.2.1 Normal Weight AggregatesSpecification C33.4.2.2 Lightweight AggregatesSpecification C331.4.3 Pigments for Integrally Co
21、lored ConcreteSpecification C979.4.4 Other ConstituentsAir-entraining agents, integral wa-ter repellents, and other constituents shall be previously estab-lished as suitable for use in concrete masonry units and shallconform to applicable ASTM standards or shall be shown bytest or experience not to
22、be detrimental to the durability of theconcrete masonry units or any material customarily used inmasonry construction.5. Physical Requirements5.1 At the time of delivery to the purchaser, units shallconform to the physical requirements prescribed in Table 1 andTable 2. All units shall be sound and f
23、ree of cracks or otherdefects that interfere with the proper placement of the unit orsignificantly impair the strength or permanence of the construc-tion. Minor cracks, incidental to the usual method of manufac-ture or minor chipping resulting from customary methods ofhandling in shipment and delive
24、ry, are not grounds for rejec-tion.NOTE 3Higher compressive strengths than those listed in Table 2 maybe specified where required by design. Consult with suppliers to determineavailability of units of higher compressive strength.NOTE 4Oven-dry densities of concrete masonry units generally fallwithin
25、 the range of 85 to 145 lbf/ft3(1360 to 2320 kg/m3). Becauseavailable densities will vary, suppliers should be consulted before speci-fying project requirements.5.1.1 When higher compressive strengths than those listedin Table 2 are specified, the tested average net area compres-sive strength of thr
26、ee units shall equal or exceed the specifiedcompressive strength, and the tested individual unit net areacompressive strength of all three units shall exceed 90 % of thespecified compressive strength.5.2 At the time of delivery to the purchaser, the linearshrinkage of units shall not exceed 0.065 %.
27、NOTE 5The purchaser is the public body or authority, association,corporation, partnership, or individual entering into a contract or agree-ment to purchase or install, or both, concrete masonry units. The time ofdelivery to the purchaser is FOB plant when the purchaser or thepurchasers agent transpo
28、rts the concrete masonry units, or at the timeunloaded at the worksite if the manufacturer or the manufacturers agenttransports the concrete masonry units.5.3 Hollow Units:5.3.1 Face shell thickness (tfs) and web thickness (tw) shallconform to the requirements prescribed in Table 1.NOTE 6Web thickne
29、ss (tw) not conforming to the requirementsprescribed in Table 1 may be approved, provided equivalent structuralcapability has been established when tested in accordance with theapplicable provisions of Test Methods E72, C1314, E519, or otherapplicable tests and the appropriate design criteria develo
30、ped is inaccordance with applicable building codes.5.4 Solid Units:5.4.1 The net cross-sectional area of solid units in everyplane parallel to the bearing surface shall be not less than 75 %of the gross cross-sectional area measured in the same plane.5.5 End Flanges:5.5.1 For units having end flange
31、s, the thickness of eachflange shall not be less than the minimum face shell thickness.NOTE 7Flanges beveled at the ends for mortarless head jointapplications that will be filled with grout are exempt from this require-ment. Flanges which are specially shaped for mortarless head jointapplications wh
32、ich have been shown by testing or field experience toprovide equivalent performance are exempt from this requirement.6. Permissible Variations in Dimensions6.1 Standard UnitsFor standard units, no overall dimen-sion (width, height, and length) shall differ by more than 618in. (3.2 mm) from the speci
33、fied dimensions.TABLE 1 Minimum Face Shells and Web RequirementsANominal Width (W) of Units,in. (mm)Face Shell Thickness (tfs),min, in. (mm)B,CWebsWeb ThicknessC(tw),min, in. (mm)Normalized Web Area (Anw),min, in.2/ft2(mm2/m2)D3 (76.2) and 4 (102)34 (19)34 (19) 6.5 (45,140)6 (152) 1 (25)34 (19) 6.5
34、(45,140)8 (203) and greater 114 (32)34 (19) 6.5 (45,140)AAverage of measurements on a minimum of 3 units when measured as described in Test Methods C140.BWhen this standard is used for units having split surfaces, a maximum of 10 % of the split surface is permitted to have thickness less than those
35、shown, but not lessthan34 in. (19.1 mm). When the units are to be solid grouted, the 10 % limit does not apply and Footnote C establishes a thickness requirement for the entire faceshell.CWhen the units are to be solid grouted, minimum face shell and web thickness shall be not less than58 in. (16 mm
36、).DMinimum normalized web area does not apply to the portion of the unit to be filled with grout. The length of that portion shall be deducted from the overall length of theunit for the calculation of the minimum web cross-sectional area.C901226.2 Particular Feature UnitsFor particular feature units
37、,dimensions shall be in accordance with the following:6.2.1 For molded face units, no overall dimension (width,height, and length) shall differ by more than 618 in. (3.2 mm)from the specified standard dimension. Dimensions of moldedfeatures shall be within 6116 in. (1.6 mm) of the specifiedstandard
38、dimensions and shall be within 6116 in. (1.6 mm) ofthe specified placement of the molded feature.NOTE 8Molded features include, but are not limited to: ribs, scores,hex-shapes, and patterns.6.2.2 For split-faced units, all non-split overall dimensionsshall differ by not more than 618 in. (3.2 mm) fr
39、om thespecified standard dimensions.6.2.3 For slump units, no overall height dimension shalldiffer by more than 618 in. (3.2 mm) from the specifiedstandard dimension.NOTE 9On faces that are split or slumped, overall dimensions willvary. Consult with suppliers to determine achievable dimensional tole
40、r-ances for products including these features.7. Finish and Appearance7.1 Where units are to be used in exposed wall construction,the face or faces that are to be exposed shall not show chips orcracks, not otherwise permitted, or other imperfections whenviewed from a distance of not less than 20 ft
41、(6.1 m) underdiffused lighting.7.1.1 Five percent of a shipment containing chips, not largerthan 1 in. (25.4 mm) in any dimension, or cracks not wider than0.02 in. (0.5 mm) and not longer than 25 % of the nominalheight of the unit, is permitted.7.2 The color and texture of units shall be specified b
42、y thepurchaser. The finished surfaces that will be exposed in placeshall conform to an approved sample, consisting of not lessthan four units, representing the range of texture and colorpermitted.NOTE 10Concrete masonry units are produced using a wide variety ofnatural aggregates and other materials
43、. As such, slight variations inherentfrom natural materials should be expected. Since specifying units andapproving samples can take place several months prior to production ofactual units for a project, slight variations in appearance from theapproved sample are to be expected.7.3 A shipment shall
44、not contain more than 5 % of units,including broken units, that do not meet the requirements of6.1, 7.1, and 7.1.1.8. Sampling and Testing8.1 The purchaser or authorized representative shall beaccorded proper facilities to inspect and sample the units at theplace of manufacture from the lots ready f
45、or delivery.8.2 Sample and test units in accordance with Test MethodsC140.8.3 Total linear drying shrinkage shall be based on tests ofconcrete masonry units made with the same materials, concretemix design, manufacturing process, and curing method, con-ducted in accordance with Test Method C426 and
46、not morethan 24 months prior to delivery.9. Compliance9.1 If a sample fails to conform to the specified require-ments, the manufacturer shall be permitted to remove unitsfrom the shipment. A new sample shall be selected by thepurchaser from remaining units from the shipment with asimilar configurati
47、on and dimension and tested. If the secondsample meets the specified requirements, the remaining portionof the shipment represented by the sample meets the specifiedrequirements. If the second sample fails to meet the specifiedrequirements, the remaining portion of the shipment repre-sented by the s
48、ample fails to meet the specified requirements.NOTE 11Unless otherwise specified in the purchase order, the cost oftests is typically borne as follows: (1) if the results of the tests show thatthe units do not conform to the requirements of this specification, the costis typically borne by the selle
49、r; (2) if the results of the tests show that theunits conform to the specification requirements, the cost is typically borneby the purchaser.10. Keywords10.1 absorption; compressive strength; concrete masonryunits; equivalent web thickness; face shell; flange; lightweight;linear drying shrinkage; loadbearing; medium weight; normalweight; websTABLE 2 Strength, Absorption, and Density Classification RequirementsDensity Classification Oven-Dry Densityof Concrete, lb/ft3(kg/m3)Maximum WaterAbsorption, lb/ft3(kg/m3)Minimum Net AreaCompressive S
