1、Designation: E518/E518M 10Standard Test Methods forFlexural Bond Strength of Masonry1This standard is issued under the fixed designation E518/E518M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last revision. A numbe
2、r in parentheses indicates the year of last reapproval.A superscript epsilon () 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 These test methods cover determination of the flexuralbond
3、 strength of unreinforced masonry assemblages. Twoprocedures are provided:1.1.1 Test Method ASimply supported beam with third-point loading.1.1.2 Test Method BSimply supported beam with uniformloading.1.2 These test methods cover the application of the testsusing either inch-pound or SI units. The v
4、alues stated in eitherSI units or inch-pound units are to be regarded separately asstandard. Within the text, the inch-pound units are shown inbrackets. The values stated in each system may not be exactequivalents; therefore, each system shall be used independentlyof the other. Combining values from
5、 the two systems mayresult in nonconformance with the standard.1.3 This 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 applic
6、a-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C67 Test Methods for Sampling and Testing Brick andStructural Clay TileC78 Test Method for Flexural Strength of Concrete (UsingSimple Beam with Third-Point Loading)C140 Test Methods for Sampling and Testing Co
7、ncreteMasonry Units and Related UnitsC270 Specification for Mortar for Unit MasonryC778 Specification for Standard SandE4 Practices for Force Verification of Testing MachinesE72 Test Methods of Conducting Strength Tests of Panelsfor Building ConstructionE575 Practice for Reporting Data from Structur
8、al Tests ofBuilding Constructions, Elements, Connections, and As-semblies3. Significance and Use3.1 These test methods are intended to provide simplifiedand economical means for gathering comparative research dataon the flexural bond strength developed with different types ofmasonry units and mortar
9、 or for the purpose of checking jobquality control (materials and workmanship).NOTE 1These test methods are not intended for use in establishingdesign stresses. For this purpose, Methods E72 should be used.4. Apparatus4.1 Testing Machine, conforming to the requirements ofPractices E4.4.2 Test Method
10、 AThe third-point loading method isillustrated in Fig. 1. The minimum span between supports shallnot be less than 2.5 multiplied by the average depth of thespecimen. The distance between each support and the adjacentdistributed point load shall be one-third of the span length63 mm 0.1 in. Steel rods
11、 with a maximum diameter of 25mm 1 in. shall be used to support the specimen and apply theload. The steel rods shall extend over the full width of thespecimen and shall have the same nominal diameter.NOTE 2The loading apparatus is intended to be similar to that used inTest Method C78 to reduce the n
12、eed for redundant testing equipment.4.3 Test Method BThe uniform loading method is illus-trated in Fig. 2. The minimum span between supports shall notbe less than 2.5 multiplied by the average depth of thespecimen. Uniformly distributed transverse load shall be ap-plied by air pressure using an air
13、bag over the full surface of thespecimen. The air bag reaction frame shall fully contact onesurface of the air bag and shall be sufficiently stiff as to notdeflect more than the span divided by 600 during testing.NOTE 3Air bags manufactured using 0.5 mm 0.02 in. thick polyvi-nyl chloride have been s
14、uccessfully used with this test. When testing1These test methods are under the jurisdiction of ASTM Committee C15 onManufactured Masonry Units and are the direct responsibility of SubcommitteeC15.04 on Research.Current edition approved June 1, 2010. Published July 2010. Originally approvedin 1974. L
15、ast previous edition approved in 2009 as E518 09. DOI: 10.1520/E0518_E0518M-10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page o
16、nthe 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.specimens constructed with a high bond-strength mortar, or whosethickness is greater than a nominal 1
17、00 mm 4 in., the applied loadrequired to fail the specimen may be such as to rupture the seams of theair bag. In such cases Test Method A is recommended.5. Sampling and Testing5.1 Masonry UnitsRepresentative masonry units shall besampled and tested in accordance with the following applicablemethods:
18、 Test Methods C67 for brick, or Test Methods C140for concrete masonry units. Minimum tests required shall becompressive strength, and initial rate of absorption for brick orabsorption for concrete masonry units.5.2 MortarOne of the types of mortar in SpecificationC270 shall be used, or the mortar sh
19、all conform to thatspecified for the construction. Sand sieve analysis shall beperformed and recorded, except when ASTM C778 standardsand is used. If ASTM C778 standard sand is used, the recordshall identify the sand as 2030 sand, graded sand, or a blendof indicated proportions of each sand by weigh
20、t.5.2.1 Mortar for prism fabrication shall be mixed to aworkable consistency. The compressive strength, initial flow,and water retention of the mortar shall be determined inaccordance with the requirements of Specification C270, ex-cept that the cubes molded for the compressive strength test,after m
21、oist curing in the molds for 24 h, shall be released andstored in the same atmosphere as the prisms as specified inSection 7. The following physical properties of the mortar shallbe determined and recorded:5.2.2 Compressive strength (average of three cubes),5.2.3 Initial flow (laboratory-mixed morta
22、r only),5.2.4 Flow after suction (water retention) (laboratory-mixedmortar only).6. Test Specimens6.1 A minimum of five test specimens shall be constructedas stack-bonded prisms, at least 460 mm 18 in. high withmortar joints 10 6 1.5 mm 38 6116 in. in thickness. TheFIG. 1 The Third-Point Loading Met
23、hod (Test Method A)FIG. 2 The Uniform Loading Method (Test Method B)E518/E518M 102number of courses in each specimen shall be such as to permitlocating supports and loading points midway between joints forTest Method A tests (4, 7, 10, 13, or 16 courses, depending onface heights of units), and to pr
24、ovide for a span-to-depth ratiothat exceeds 2.5. When the test is for the purpose of determin-ing the quality of materials and workmanship during construc-tion, the specimens shall be constructed at the site by themasons involved, utilizing the materials on the site and thesame masonry construction
25、techniques.6.2 Applicable portions of the following procedures shall beobserved:6.2.1 Set units on a firm, flat surface without the use ofmortar, leaving not less than 50-mm 2-in. spaces betweenstretchers.6.2.2 Place a full or face shell mortar bed (in accordancewith job specification) on all units
26、without furrowing.6.2.3 Immediately place the next course of units on themortar bed and tap each unit to level.Align at least one verticalface of each prism to a plane using a level or other means.(Note 4).6.2.4 Repeat steps 6.2.2 and 6.2.3 until the prisms are therequired number of courses high. To
27、ol or otherwise finish thejoints as specified.NOTE 4A convenient method of aligning one face is to use a jig asillustrated in Fig. 3.7. Handling and Curing Conditions7.1 Unless otherwise specified, all prisms shall be cured for28 days. The prisms together with corresponding mortar cubesshall be cure
28、d in laboratory air maintained at a temperature of24 6 8C 75 6 15F, with a relative humidity between 30and 70 %, and free of drafts. These environmental conditionsgenerally will not require special air-conditioning equipment.A continuous graphical record of temperature and humiditywill suffice to de
29、tect unusual dryness or excessive moisture,together with unusual fluctuations of temperature.7.1.1 Where prisms are made during construction at the jobsite, they shall be constructed in a place where they will not bedisturbed, but will be subjected to air conditions similar tothose in the masonry st
30、ructure.8. Procedure8.1 Place the test specimen horizontally on its supports as asimply supported beam. If full contact is not obtained betweenthe specimen and the load-applying blocks and supports,compressible shims or a bed of gypsum capping material shallFIG. 3 Use of a Jig to Align One Face of a
31、 Prism to a PlaneE518/E518M 103be used to level and seat the specimen thereby ensuring theuniform application of load. If compressible shims are used,they shall be made of leather or similar compressible materialof uniform-thickness, not less than 6 mm 14 in. thick, 25 to 50mm 1 to 2 in. in width, a
32、nd shall extend across the full widthof the specimen.8.2 Apply the load at a uniform rate of travel of the movinghead such that the total load is applied in not less than 1 normore than 3 min.8.3 Record the maximum applied load in Newtons (pounds)as P and the location of the break.9. Calculation9.1
33、For specimens built with solid masonry units (75 % ormore net area), calculate the gross area modulus of rupture asfollows (See Note 5):9.1.1 For Test Method A, with third-point loading:R 5P 1 0.75 Ps!lbd2(1)where:R = gross area modulus of rupture, MPa psi,P = maximum applied load indicated by the t
34、estingmachine, N lbf,Ps= weight of specimen, N lbf,l = span, mm in.,b = average width of specimen, mm in., andd = average depth of specimen, mm in.9.1.2 For Test Method B, with uniform loading:R 50.75 P 1 Ps!lbd2(2)where the terms are the same as those described in 9.1.1.9.2 For specimens built with
35、 hollow masonry units (lessthan 75 % net area), calculate the net area modulus of ruptureas follows (See Note 5):9.2.1 For Test Method A, with third-point loading:R 50.167 P 1 0.125 Ps!lS(3)where:S = section modulus of actual net bedded area, mm3in.3.9.2.2 For Test Method B, with uniform loading:R 5
36、0.125 P 1 Ps!lS(4)where S is the same as in 9.2.1.NOTE 5The equations for determining the modulus of rupture valuesin 9.1 and 9.2 assume that the location of the failure plane occurs at themid-span of the specimen. Where the failure location is other thanmid-span, the use of these equations for dete
37、rmining the modulus ofrupture will not be entirely accurate. Where a more precise assessment ofthe specimens modulus of rupture values is deemed appropriate, a morethorough analysis using accepted engineering mechanics should beemployed.9.3 If the failure occurs in a joint outside of the middle thir
38、dof the span length for Method A, discard the test results.10. Report10.1 The report shall be prepared in conformance withPractice E575 and shall include the following:10.1.1 Identification number,10.1.2 Average width of specimen to the nearest 1.0 mm0.05 in.,10.1.3 Average depth of specimen to the
39、nearest 1.0 mm0.05 in.,10.1.4 Weight of specimen, N lbf,10.1.5 Method of applying load (Method A or B),10.1.6 Maximum applied load, N lbf,10.1.7 Individual and average gross or net area moduli ofrupture calculated to the nearest MPa psi; standard deviation;and coefficient of variation.10.1.8 Curing
40、history and age of specimen,10.1.9 Defects in specimen,10.1.10 Description of failure,10.1.11 Type and mix design of mortar,10.1.12 Compressive strength of mortar, kPa psi,10.1.13 Initial flow of mortar as used (laboratory-mixedmortar only),10.1.14 Water retention of mortar (laboratory-mixed mortaro
41、nly),10.1.15 Physical properties of masonry units, and10.1.16 Sketch or photograph of masonry unit showing coreconfiguration and mortar bedded area, full or face shell.10.1.17 Results of the sand sieve analysis or, ifASTM C778sand is used, identify which of the defined sands were used.11. Precision
42、and Bias11.1 No statement is made either on the precision or on thebias of these test methods due to the variety of materials andcombinations of materials involved. Sufficient test data for allmaterials and combinations of materials are not presentlyavailable to permit the development of precision a
43、nd biasstatements.12. Keywords12.1 flexural bond strength; masonry units; mortar; simplysupported beam; stack bonded prism; third point loading;uniform loadE518/E518M 104SUMMARY OF CHANGESCommittee C15 has identified the location of selected changes to this standard since the last issue (E518 09)tha
44、t may impact the use of this standard. (Approved June 1, 2010.)(1) Changes were incorporated into 1.2 and throughout thestandard to permit the application of these test methods usingeither SI or inch-pound units.(2) Clarifying revisions were incorporated into 4.2 and 4.3.(3) Fig. 1 and Fig. 2 were m
45、odified to permit supporting spansgreater than or equal to 2.5 multiplied by the depth of thespecimen.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that de
46、termination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved
47、or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel t
48、hat your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprint
49、s (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).E518/E518M 105
