1、Designation: C1314 09Standard 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 p
2、arentheses 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 determiningth
4、e 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 Th
5、is 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 Documen
6、ts2.1 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-CementConcreteC
7、144 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 GroutC1093
8、 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 pris
10、ms 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 o
11、f 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 constructionw
12、hen 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, 2009.
14、Published December 2009. Originallyapproved in 1995. Last previous edition approved in 2007 as C1314 07. DOI:10.1520/C1314-09.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information,
15、 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. Su
16、chresearch 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 mater
17、ials, 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 surface
18、 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 const
19、ruction. 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 d
20、etermined.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 units
21、 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 or
22、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 of
23、 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 prisms
24、 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 properl
25、y cappedand tested. Also, the smaller prism will be less likely to be affected byplate bending effects during testing, as described in Note 8, and willtherefore provide a more accurate assessment of the strength of thematerials in the masonry prism. For these reasons, the use of reducedlength prisms
26、 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 correspon
27、ding 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,se
28、al the moisture-tight bag around the prism.5.9 Grouted Prisms.5.9.1 When prisms are used for field quality control orassurance, construct prisms at the same time as the correspond-ing construction, and grout prisms when the correspondingconstruction is being grouted. When prisms are used for otherFI
29、G. 1 Masonry Prism ConstructionFIG. 2 Reduction of Hollow Units Prior to Prism ConstructionC1314 092purposes, grout prisms not less than 4 h nor more than 48 hfollowing the construction of the prisms.5.9.2 Where the corresponding construction is to be solidlygrouted, solidly grout the prisms. Use gr
30、out representative ofthat used in the corresponding construction. Before placinggrout, remove mortar droppings from the grout space. Usegrout consolidation and reconsolidation procedures represen-tative of those used in the construction. Place additional groutinto the prisms as necessary after each
31、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 perimeter 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
32、 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 groutbetween similar wythes are to be grouted, use similar masonryunits as forms to confine the grout during placement. Braceforms to prevent displacement during gro
33、uting. Grout asdescribed in 5.9.2.5.9.5 Immediately following the grouting operation, resealthe moisture-tight bag around the prism.5.10 Keep 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 pr
34、ior to testing.5.11 Store an indicating maximum-minimum thermometerwith the sample and record the maximum and minimumtemperatures experienced 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
35、 with Practice C1532.6.2 Prior to transporting constructed prisms and field-removed masonry specimens, strap or clamp each prism orspecimen to prevent damage during handling and transporta-tion. Secure prisms and specimens to prevent jarring, bounc-ing, or tipping over during transporting.6.3 Transp
36、ort prisms and masonry specimens in accordancewith Practice C1532.6.4 For field-removed masonry specimens, after the speci-mens have been transported to the laboratory, obtain prismsfrom the masonry specimens using procedures outlined inPractice C1587.7. Curing7.1 After the initial 48 h of curing fo
37、r constructed prisms,maintain the bagged prisms in an area with a temperature of 756 15F (24 6 8C). Two days prior to testing, remove themoisture-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 ma
38、sonry, 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 testing.7.3 Prisms shall not be oven-dried or otherwise exposed totemperatures exceeding storage temperature requirements atany time prior to testing.7.4 Visib
39、le moisture shall not be present on the surface ofthe prisms at the time of testing. Extend storage time as neededto ensure dry surface conditions 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
40、 bedetermined from the time of laying units for ungrouted prisms,and from the time of grouting for grouted prisms.8. Measurements and Determination 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
41、 in. (1 mm). Determine the length andwidth by averaging the four measurements of each dimension.Measure the height of the prism at the center 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 masonryspecime
42、ns, perform additional measurements as needed todocument the condition and dimensions of the specimen.NOTE 4Prisms obtained from field-removed masonry specimens willhave many different sizes, shapes, and configurations. These variations area result of differing bonding arrangements, mortaring or joi
43、ning practices,presence of reinforcement and other accessories in conjunction with themasonry in service, and of techniques used to remove the specimens fromwall assemblies. These variations may create non-uniform prism dimen-sions along its length or in its cross-section. As such, additional measur
44、e-ments are often required to adequately document the condition of theprism and to communicate that condition to readers of the test report.8.2 Net Cross-Sectional Area:8.2.1 Constructed PrismsTake the net cross-sectional areaof ungrouted prisms as the net cross-sectional area of masonryunits, deter
45、mined by measurement or from a representativesample of units tested in accordance with Test Methods 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. De
46、termine net cross-sectional area of fullygrouted prisms by multiplying the length and width of theprism (see 8.1).FIG. 3 Prism Measurement LocationC1314 093NOTE 5Net area determined by Test Methods C140 for hollowconcrete units is usually slightly different from the minimum net cross-sectional area
47、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 % of the gross cross-sectional areaas 100 % solid.8.2.2 Prisms Obtained from Field-Removed MasonrySpecimensUse methods identified above to determine netarea if ap
48、propriate. 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 bear
49、ing area that exists for the prism at whateverlocation that occurs.NOTE 6While constructed prisms are required to be fully-bedded withmortar, prisms obtained from field-removed masonry specimens, particu-larly for hollow masonry, will often have only the face shells of the hollowunits mortared. For such prisms, if any mortar on the top and bottombearing surfaces of the prisms are removed to result in full bearing acrossthe unit cross-section, the minimum cross-section will typically occur atan intermediate mortar bed joint. For face shell bedded sections, mul
