1、Designation: C1314 11aStandard Test Method forCompressive Strength of Masonry Prisms1This standard is issued under the fixed designation C1314; 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 test method covers procedures for masonry prismconstruction and testing, and procedures for determining thecompressive strength of masonry,
3、 fmt, used to determinecompliance with the specified compressive strength of ma-sonry, f 8m. When this test method is used for researchpurposes, the construction and test procedures within serve asa guideline and provide control parameters.1.2 This test method also covers procedures for determiningt
4、he compressive strength of prisms obtained from field-removed masonry specimens.1.3 The values 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.1.4 T
5、his standard does not purport to address all of thesafety concerns, if any, associated with its use. It 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 Docume
6、nts2.1 ASTM Standards:2C67 Test Methods for Sampling and Testing Brick andStructural Clay TileC136 Test Method for Sieve Analysis of Fine and CoarseAggregatesC140 Test Methods for Sampling and Testing ConcreteMasonry Units and Related UnitsC143/C143M Test Method for Slump of Hydraulic-CementConcrete
7、C144 Specification for Aggregate for Masonry MortarC270 Specification for Mortar for Unit MasonryC476 Specification for Grout for MasonryC780 Test Method for Preconstruction and ConstructionEvaluation of Mortars for Plain and Reinforced UnitMasonryC1019 Test Method for Sampling and Testing GroutC109
8、3 Practice for Accreditation of Testing Agencies forMasonryC1532 Practice for Selection, Removal, and Shipment ofManufactured Masonry Units and Masonry Specimensfrom Existing ConstructionC1552 Practice for Capping Concrete Masonry Units, Re-lated Units and Masonry Prisms for Compression TestingC1587
9、 Practice for Preparation of Field Removed Manufac-tured Masonry Units and Masonry Specimens for TestingE105 Practice for Probability Sampling of MaterialsE111 Test Method for Youngs Modulus, Tangent Modulus,and Chord Modulus3. Terminology3.1 Definitions:3.1.1 seta set consists of at least three pri
10、sms constructedof the same material and tested at the same age.3.2 Notations:3.2.1 f 8mspecified compressive strength of masonry.3.2.2 fmtcompressive strength of masonry.3.2.3 hpprism height.3.2.4 tpleast actual lateral dimension of prism.4. Significance and Use4.1 This test method provides a means
11、of verifying thatmasonry materials used in construction result in masonry thatmeets the specified compressive strength.4.2 This test method provides a means of evaluating com-pressive strength characteristics of in-place masonry construc-tion through testing of prisms obtained from that construction
12、when sampled in accordance with Practice C1532. Decisionsmade in preparing such field-removed prisms for testing,determining the net area, and interpreting the results ofcompression tests require professional judgment.4.3 If this test method is used as a guideline for performingresearch to determine
13、 the effects of various prism constructionor test parameters on the compressive strength of masonry,1This test method is under the jurisdiction of ASTM Committee C15 onManufactured Masonry Units and is the direct responsibility of SubcommitteeC15.04 on Research.Current edition approved Dec. 1, 2011.
14、 Published December 2011. Originallyapproved in 1995. Last previous edition approved in 2011 as C1314 11. DOI:10.1520/C1314-11A.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume informatio
15、n, 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 Conshohocken, PA 19428-2959, United States.deviations from this test method shall be reported.
16、Suchresearch prisms shall not be used to verify compliance with aspecified compressive strength of masonry.NOTE 1The testing laboratory performing this test method should beevaluated in accordance with Practice C1093.4.3.1 Appendix X2 includes guidance information for theresearcher on aspects of mat
17、erials, construction, and analysis.5. Masonry Prism Construction5.1 Construct prisms of units representative of those used inthe construction. If units have flutes or ribs that project12 in.(12.5 mm) or more from the surface of the unit, remove thoseflutes or ribs by saw cutting flush with the surfa
18、ce of the unitat the base of the flute or rib. When prisms are used for fieldquality control or assurance, record the location in the structurethat corresponds to the set of prisms constructed.NOTE 2Building codes or project specifications may require a set ofprisms for a given square footage of con
19、struction. Recording the locationof the structure that corresponds to a set of prisms allows the test resultsto be attributed to a particular portion of the structure.5.2 Construct a set of prisms for each combination ofmaterials and each test age at which the compressive strengthof masonry is to be
20、 determined.5.3 Build each prism in an opened, moisture-tight bag largeenough to enclose and seal the completed prism. Constructprisms on a flat, level base. Construct prisms in a locationwhere they will remain undisturbed until transported fortesting.5.4 Construct prisms as shown in Fig. 1 with uni
21、ts laid instack bond in stretcher position. Orient units in the prism as inthe corresponding construction. At the time of prism construc-tion, the surfaces of the units shall be free of moisture. Wherethe corresponding construction is of multi-wythe masonryhaving wythes composed of different units o
22、r mortar, buildprisms representative of each different wythe and test sepa-rately.5.5 Build prisms with full-size or reduced length units. Anyrequired saw cutting shall be performed on units prior to prismconstruction. The moisture content(s) of units used to constructprisms shall be representative
23、of those used in construction.Prisms composed of units that contain closed cells shall have atleast one complete cell with one full-width cross web on eitherend (see Fig. 2). Prisms composed of units without closed cellsshall have as symmetrical a cross section as possible. Theminimum length of pris
24、ms shall be 4 in. (100 mm).NOTE 3When using larger masonry units, experience has shown thatreducing the length of these units prior to prism construction makes theirhandling and transportation easier. Thus, these reduced length unit prismsare less likely to be damaged and are more likely to be prope
25、rly cappedand tested. Also, the smaller prism will be less likely to be affected byplate bending effects during testing, as described in Note 9, and willtherefore provide a more accurate assessment of the strength of thematerials in the masonry prism. For these reasons, the use of reducedlength pris
26、ms is encouraged.5.6 Build masonry prisms with full mortar beds (mortar allwebs and face shells of hollow units). Use mortar representa-tive of that used in the corresponding construction. Use mortarjoint thickness and a method of positioning and aligning units,that are representative of the corresp
27、onding construction. Usemortar joints that are cut flush. For prisms to be grouted,remove mortar “fins” that protrude into the grout space.5.7 Build prisms a minimum of two units high with aheight-to-thickness ratio, hp/tp, between 1.3 and 5.0.5.8 Immediately following the construction of the prism,
28、seal the moisture-tight bag around the prism.5.9 Grouted Prisms.5.9.1 When prisms are fabricated for field quality control orassurance, build prisms at the same time as the correspondingconstruction, and grout prisms when the corresponding con-struction is being grouted. When prisms are used for oth
29、erFIG. 1 Masonry Prism ConstructionFIG. 2 Reduction of Hollow Units Prior to Prism ConstructionC1314 11a2purposes, grout prisms not less than 4 h nor more than 48 hfollowing the construction of the prisms.NOTE 4Testing of prisms may be part of a projects field qualitycontrol or assurance program. Th
30、ese prisms are intended to be represen-tative of a constructed masonry element such as a wall, column, pilaster,or beam. They are built as companions to the masonry element at a jobsitewhere the masonry element is site-constructed, or within a factory or shopwhere the element is shop-built. Prisms m
31、ay also be fabricated in alaboratory for research purposes.5.9.2 Where the corresponding construction is to be solidlygrouted, solidly grout the prisms. Use grout representative ofthat used in the corresponding construction. Before placinggrout, remove mortar droppings from the grout space. Usegrout
32、 consolidation and reconsolidation procedures represen-tative of those used in the construction. Place additional groutinto the prisms as necessary after each consolidation. Screedoff excess and finish the grout so that it is level with the top ofthe prism and in contact with the units at the perime
33、ter of thegrout space. Grouted prisms shall contain no reinforcement.5.9.3 Where the corresponding construction is to be par-tially grouted, construct two sets of prisms; grout one set solidas described in 5.9.2 and leave the other set ungrouted.5.9.4 Where open-end units or prisms containing groutb
34、etween similar wythes are to be grouted, use similar masonryunits as forms to confine the grout during placement. Braceforms to prevent displacement during grouting. Grout asdescribed in 5.9.2.5.9.5 Immediately following the grouting operation, resealthe moisture-tight bag around the prism.5.10 Keep
35、 all prisms from freezing. Do not disturb or moveprisms for the first 48 h after construction and grouting. Keepprisms in the moisture-tight bags until 48 h prior to testing.5.11 Store an indicating maximum-minimum thermometerwith the sample and record the maximum and minimumtemperatures experienced
36、 during the initial 48-h period.6. Obtaining and Transporting Masonry Prisms6.1 For field-removed masonry specimens, select and re-move specimens in accordance with Practice C1532.6.2 Prior to transporting constructed prisms and field-removed masonry specimens, strap or clamp each prism orspecimen t
37、o prevent damage during handling and transporta-tion. Secure prisms and specimens to prevent jarring, bounc-ing, or tipping over during transporting.6.3 Transport prisms and masonry specimens in accordancewith Practice C1532.6.4 For field-removed masonry specimens, after the speci-mens have been tra
38、nsported to the laboratory, obtain prismsfrom the masonry specimens using procedures outlined inPractice C1587.7. Curing7.1 After the initial 48 h of curing for constructed prisms,maintain the bagged prisms in an area with a temperature of 756 15F (24 6 8C). Two days prior to testing, remove themois
39、ture-tight bags and continue storing at a temperature of 756 15F (24 6 8C) and a relative humidity less than 80 %.7.2 For prisms obtained from field-removed masonry, storewithin the laboratory at a temperature of 75 6 15F (24 6 8C)and a relative humidity less than 80 % for at least two daysprior to
40、testing.7.3 Prisms shall not be oven-dried or otherwise exposed totemperatures exceeding storage temperature requirements atany time prior to testing.7.4 Visible moisture shall not be present on the surface ofthe prisms at the time of testing. Extend storage time as neededto ensure dry surface condi
41、tions of the prisms at the time oftesting.7.5 Test prisms at an age of 28 days or at the designated testages. Test a set of prisms at each age. Prism age shall bedetermined from the time of laying units for ungrouted prisms,and from the time of grouting for grouted prisms.8. Measurements and Determi
42、nation of Net Area8.1 Measuring PrismsAs shown in Fig. 3, measure thelength and width at the edges of the top and bottom faces of theprisms to the nearest 0.05 in. (1 mm). Determine the length andwidth by averaging the four measurements of each dimension.Measure the height of the prism at the center
43、 of each face to thenearest 0.05 in. (1 mm). Determine the height by averaging thefour measurements.8.1.1 For prisms obtained from field-removed masonryspecimens, perform additional measurements as needed todocument the condition and dimensions of the specimen.NOTE 5Prisms obtained from field-remove
44、d masonry specimens willhave many different sizes, shapes, and configurations. These variations area result of differing bonding arrangements, mortaring or joining practices,presence of reinforcement and other accessories in conjunction with themasonry in service, and of techniques used to remove th
45、e specimens fromwall assemblies. These variations may create non-uniform prism dimen-sions along its length or in its cross-section. As such, additional measure-ments are often required to adequately document the condition of theprism and to communicate that condition to readers of the test report.8
46、.2 Net Cross-Sectional Area:8.2.1 Constructed PrismsTake the net cross-sectional areaof ungrouted prisms as the net cross-sectional area of masonryunits, determined by measurement or from a representativeFIG. 3 Prism Measurement LocationC1314 11a3sample of units tested in accordance with Test Method
47、s C140for concrete masonry and with Test Methods C67 for claymasonry. If cut units are used for prism construction, determinethe net cross-sectional area from additional units cut in asimilar manner. Determine net cross-sectional area of fullygrouted prisms by multiplying the length and width of the
48、prism (see 8.1).NOTE 6Net area determined by Test Methods C140 for hollowconcrete units is usually slightly different from the minimum net cross-sectional area because unit face shells and webs are typically tapered.8.2.1.1 Consider clay masonry units whose net cross-sectional area is at least 75 %
49、of the gross cross-sectional areaas 100 % solid.8.2.2 Prisms Obtained from Field-Removed MasonrySpecimensUse methods identified above to determine netarea if appropriate. Net area for prisms obtained from field-removed masonry specimens is considered to be minimumbearing area. If prisms are not of uniform length or widththroughout the height of the specimen, or if mortared surfacesare not fully bedded, use professional judgment to determinethe minimum bearing area that exists for the prism at whateverlocation that occurs.NOTE 7While constructed prisms are r
