1、Designation: C140 12 C140 12aStandard Test Methods forSampling and Testing Concrete Masonry Units and RelatedUnits1This standard is issued under the fixed designation C140; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year o
2、f last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 These test methods provide various testing procedures commonly used for evaluating characteristics of concrete maso
3、nryunits and related concrete units. Methods are provided for sampling, measurement of dimensions, compressive strength,absorption, unit weight (density), moisture content, flexural load, and ballast weight. Not all methods are applicable to all unittypes, however.1.2 Specific testing and reporting
4、procedures are included in annexes to these test methods for the following specific unit types:Annex A1Concrete masonry units (Specifications C90, C129)Annex A2Concrete and calcium silicate brick(Specifications C55, C73, C1634)Annex A3Segmental retaining wall units (Specification C1372)Annex A4Concr
5、ete interlocking paving units(Specification C936/C936M)Annex A5Concrete grid paving units (Specification C1319)Annex A6Concrete roof pavers (Specification C1491)Annex A7Dry-cast articulating concrete block(Specification D6684)1.3 The test procedures included in these test methods are also applicable
6、 to other types of units not referenced in these testmethods, but specific testing and reporting requirements for those units are not included.1.4 These test methods include the following sections:SectionScope 1Referenced Documents 2Terminology 3Significance and Use 4Sampling 5Measurement of Dimensi
7、ons 6Compressive Strength 7Absorption 8Calculations 9Report 10Keywords 111 These test methods are under the jurisdiction of ASTM Committee C15 on Manufactured Masonry Units and are the direct responsibility of Subcommittee C15.03 onConcrete Masonry Units and Related Units.Current edition approved Fe
8、b. 1, 2012Aug. 1, 2012. Published February 2012September 2012. Originally approved in 1938. Last previous edition approved in 20112012as C140 11a.C140 12. DOI: 10.1520/C0140-12.10.1520/C0140-12A.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an ind
9、ication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be
10、considered the official document.*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 States1SectionAnnexesTest ProceduresConcrete Masonry Units Annex A1Concrete and Calcium Silicat
11、e Brick Annex A2Segmental RetainingWall UnitsAnnex A3Concrete Interlocking Paving Units Annex A4Concrete Grid PavingUnitsAnnex A5Concrete Roof Pavers Annex A6Dry-Cast ArticulatingConcrete BlockAnnex A7Determining Plate ThicknessRequirements forCompression TestingAnnex A8Worksheet and Test Report for
12、Concrete Masonry UnitsAppendix X1NOTE 1The testing laboratory performing these test methods should be evaluated in accordance with Practice C1093.1.5 The values stated in inch-pound units are to be regarded as the standard, except in Annex A4, where either SI units orinch-pound units are to be regar
13、ded separately as standard. The values given in parentheses throughout are mathematicalconversions to SI units that are provided for information only and are not considered standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the r
14、esponsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C55 Specification for Concrete Building BrickC73 Specification for Calcium Silicate Brick (S
15、and-Lime Brick)C90 Specification for Loadbearing Concrete Masonry UnitsC129 Specification for Nonloadbearing Concrete Masonry UnitsC143/C143M Test Method for Slump of Hydraulic-Cement ConcreteC936/C936M Specification for Solid Concrete Interlocking Paving UnitsC1093 Practice for Accreditation of Tes
16、ting Agencies for MasonryC1232 Terminology of MasonryC1319 Specification for Concrete Grid Paving UnitsC1372 Specification for Dry-Cast Segmental Retaining Wall UnitsC1491 Specification for Concrete Roof PaversC1552 Practice for Capping Concrete Masonry Units, Related Units and Masonry Prisms for Co
17、mpression TestingC1634 Specification for Concrete Facing BrickD6684 Specification for Materials and Manufacture of Articulating Concrete Block (ACB) Revetment SystemsE4 Practices for Force Verification of Testing MachinesE6 Terminology Relating to Methods of Mechanical Testing3. Terminology3.1 Termi
18、nology defined in Terminologies C1232 and E6 shall apply for these test methods.4. Significance and Use4.1 These test methods provide general testing requirements for application to a broad range of concrete products. Those generaltesting requirements are included in the body of this standard.NOTE 2
19、Consult manufacturer, supplier, product specifications, or other resources for more specific measurement or testing guidelines for thoseproducts not addressed with the annex of this standard.4.2 These test methods provide specific testing requirements in two distinct sections, the requirements appli
20、cable to all unitscovered by these test methods and those applicable to the specific unit types. The requirements applicable to all units are includedin the body of these test methods and those applicable to the specific unit types are included within the annexes.5. Sampling5.1 Selection of Test Spe
21、cimens : Specimens:2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.C140 12a25.1.1 For purposes of testing,
22、 full-sized units shall be selected by the purchaser or authorized representative. The selectedspecimens shall be of similar configuration and dimensions. Specimens shall be representative of the whole lot of units from whichthey are selected.5.1.2 The term “lot” refers to any number of concrete mas
23、onry units of any configuration or dimension manufactured by theproducer using the same materials, concrete mix design, manufacturing process, and curing method.5.2 Number of Specimens:5.2.1 Unless specified otherwise in the applicable annex, a set of units shall consist of six full-size units.5.2.2
24、 Unless specified otherwise in the applicable annex, for the compressive strength, absorption, unit weight (density), andmoisture content determinations, one set of units shall be selected from each lot of 10 000 units or fraction thereof and two setsof units from each lot of more than 10 000 and le
25、ss than 100 000 units. For lots of more than 100 000 units, one set of units shallbe selected from each 50 000 units or fraction thereof contained in the lot. Additional specimens shall be taken if directed by thepurchaser.5.3 Remove loose material from the specimens (including the cores) prior to d
26、etermining the received weight.NOTE 3An abrasive stone or wire brush is typically used to remove loose material.5.4 IdentificationMark each specimen so that it may be identified at any time. Markings shall cover not more than 5 % of thesurface area of the specimen.5.5 Received WeightWeigh each speci
27、men immediately after sampling and marking, and record as Wr (received weight).Record time and place Wr was measured.NOTE 4Received weights often have direct relationships with other unit properties and are therefore a useful method of evaluating results or forsorting purposes. The weight of a concr
28、ete masonry unit and related unit changes with time and exposure conditions, primarily as a result of the moisturewithin the unit. Therefore, to understand the context of a received weight value, it is also important to understand the point in time and the frame ofreference when that weight was dete
29、rmined. “Time and place” should not refer to when and where the unit was sampled but when and where the receivedweights were determined. In addition to date and time references, it is also important to know if those weights were determined after units reachedequilibrium with lab environment, or befo
30、re units were shipped, or after delivery to the job site, and so forth.6. Measurement of Dimensions6.1 Apparatus:6.1.1 Measurement DevicesDevices used to measure specimen dimensions shall have divisions not greater than 0.1 in. (2.5mm) when the dimension is to be reported to the nearest 0.1 in. (2.5
31、 mm) and not greater than 0.01 in. (0.25 mm) when thedimension is to be reported to the nearest 0.01 in. (0.25 mm).6.1.2 Measuring devices shall be readable and accurate to the division required to be reported. Accuracy shall be verified at leastonce annually. Verification record shall include date
32、of verification, person or agency performing verification, identification ofreference standard used, test points used during verification, and readings at test points.6.2 SpecimensThree full-size units shall be selected for measurement of dimensions.6.3 MeasurementsMeasure specimens in accordance wi
33、th the applicable annex of this standard. For those products notcovered by the annexes of this standard, measure overall dimensions (width, height, length) in at least two locations on oppositesides of the specimen to the nearest division required to be reported. Document location of each measuremen
34、t on a sketch orphotograph of the specimen.NOTE 5Specimens used for measurement of dimensions may be used in other tests.NOTE 6Calipers, micrometers, and steel scales and dividers of the appropriate accuracy and readability have been shown to be adequate for thesemeasurements.7. Compressive Strength
35、7.1 Test Apparatus:7.1.1 The testing machine shall have an accuracy of 61.0 % over the anticipated load range. The upper platen shall be aspherically seated, hardened metal block firmly attached at the center of the upper head of the machine. The center of the sphereshall lie at the center of the su
36、rface held in its spherical seat but shall be free to turn in any direction, and its perimeter shall haveat least 14 in. (6.3 mm) clearance from the head to accommodate specimens whose bearing surfaces are not parallel. The diameterof the upper platen (determined in accordance with Annex A8) shall b
37、e at least 6 in. (150 mm). A hardened metal bearing platemay be used beneath the specimen to minimize wear of the lower platen of the machine.7.1.2 When the bearing area of the upper platen or lower platen is not sufficient to cover the area of the specimen, a single steelplate with a thickness equa
38、l to at least the distance from the edge of the platen to the most distant corner of the specimen shallbe placed between the platen and the capped specimen. The length and width of the steel plate shall be at least 14 in. (6 mm) greaterthan the length and width of the units.7.1.3 The surfaces of the
39、 platen or plate intended for contact with the specimen shall have a hardness not less than HRC 60(BHN 620). The surfaces of the platen and plate shall not depart from plane surfaces by more than 0.001 in. (0.03 mm) in any 6in. (150 mm) dimension.C140 12a3NOTE 7Research has shown that thickness of b
40、earing plates has a significant effect on the tested compressive strength of masonry units when thebearing area of the platen is not sufficient to cover the area of the specimen. Plate bending results in nonuniform stress distributions that can influencethe failure mechanisms of the tested specimens
41、. The magnitude of this effect is controlled by the stiffness of the plate, the size of the specimen tested,and the strength of the specimen. Tested compressive strengths will typically increase with increased plate thickness and with reduced distance to thefurthest corner of the specimen. Some test
42、ing laboratories have limitations that limit the practicality of eliminating plate bending entirely. Therefore theplate thickness requirements in 7.1 are intended to provide an adequate level of accuracy in the compression test results so as to conform to the limitsof practicality of the testing lab
43、oratory.NOTE 8Annex A8 includes guidance on determining the required plate thickness based on the configuration of the test specimen and the test machine.7.1.4 The testing machine shall be verified in accordance with Practices E4 at a frequency defined by Practice C1093.7.2 Test Specimens:7.2.1 Unle
44、ss specified otherwise in the applicable annex, test three specimens in compression.7.2.2 When possible and unless specified otherwise in the applicable annex, specimens shall be full-sized units. When the unitscannot be tested full-size due to specimen configuration or testing machine requirements,
45、 reduce the specimen size in accordancewith Annex A1.7.2.3 After delivery to the laboratory, store compression specimens (unstacked and separated by not less than 0.5 in. (13 mm)on all sides) continuously in air at a temperature of 75 6 15F (24 6 8C) and a relative humidity of less than 80 % for not
46、 lessthan 48 h. Alternatively, if compression results are required sooner, store units unstacked in the same environment described abovewith a current of air from an electric fan passing over them for a period of not less than 4 h. Continue passing air over the specimensuntil two successive weighing
47、s at intervals of 2 h show an increment of loss not greater than 0.2 % of the previously determinedweight of the specimen and until no moisture or dampness is visible on any surface of the unit. Specimens shall not be subjectedto oven-drying.NOTE 9In this test method, net area (other than certain so
48、lid units, see 9.4) is determined from specimens other than those subjected to compressiontesting. The compressive strength method is based on the assumption that units used for determining net volume (absorption specimens) have the samenet volume as units used for compression testing. Sampled split
49、 face units, which have irregular surfaces, should be divided at the time they are sampledfrom the lot, such that the absorption test specimens have a net volume that is visually representative and a weight that is representative of the compressiontest specimens.7.2.4 Where saw-cutting of test specimens is allowed or required by the standard or applicable annex, sawing shall be performedin an accurate, competent manner, subjecting the specimen to as little saw vibration as possible. Use a diamond saw blade of properhardness. If the specimen is wetted
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