1、Designation: E518/E518M 10E518/E518M 15Standard 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 revi
2、sion. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 These test methods cover determination of the flexural bond strength of unreinforced masonry assemblages. Two proceduresare pr
3、ovided:1.1.1 Test Method ASimply supported beam with third-point loading.1.1.2 Test Method BSimply supported beam with uniform loading.1.2 These test methods cover the application of the tests using either inch-pound or SI units. The values stated in either SI unitsor inch-pound units are to be rega
4、rded separately as standard. Within the text, the inch-pound units are shown in brackets. Thevalues stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other.Combining values from the two systems may result in nonconformance with the standard
5、.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Do
6、cuments2.1 ASTM Standards:2C67 Test Methods for Sampling and Testing Brick and Structural Clay TileC78 Test Method for Flexural Strength of Concrete (Using Simple Beam with Third-Point Loading)C140 Test Methods for Sampling and Testing Concrete Masonry Units and Related UnitsC270 Specification for M
7、ortar for Unit MasonryC778 Specification for Standard SandC1232 Terminology of MasonryE4 Practices for Force Verification of Testing MachinesE72 Test Methods of Conducting Strength Tests of Panels for Building ConstructionE575 Practice for Reporting Data from Structural Tests of Building Constructio
8、ns, Elements, Connections, and Assemblies3. Terminology3.1 For terms used in these test methods, refer to Terminology C1232.4. Significance and Use4.1 These test methods are intended to provide simplified and economical means for gathering comparative research data on theflexural bond strength devel
9、oped with different types of masonry units and mortar or for the purpose of checking job quality control(materials and workmanship).NOTE 1These test methods are not intended for use in establishing design stresses. For this purpose, Methods E72 should be used.5. Apparatus5.1 Testing Machine, conform
10、ing to the requirements of Practices E4.1 These test methods are under the jurisdiction of ASTM Committee C15 on Manufactured Masonry Units and are the direct responsibility of Subcommittee C15.04 onResearch.Current edition approved June 1, 2010Dec. 1, 2015. Published July 2010January 2016. Original
11、ly approved in 1974. Last previous edition approved in 20092010 asE518 09.E518 10. DOI: 10.1520/E0518_E0518M-10.10.1520/E0518_E0518M-15.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume inf
12、ormation, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately
13、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 considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM Interna
14、tional, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.2 Test Method AThe third-point loading method is illustrated in Fig. 1. The minimum span between supports shall not beless than 2.5 multiplied by the average depth of the specimen. The distance between each
15、 support and the adjacent distributed pointload shall be one-third of the span length 63 mm 0.1 in. Steel rods with a maximum diameter of 25 mm 1 in. shall be usedto support the specimen and apply the load. The steel rods shall extend over the full width of the specimen and shall have the samenomina
16、l diameter.NOTE 2The loading apparatus is intended to be similar to that used in Test Method C78 to reduce the need for redundant testing equipment.5.3 Test Method BThe uniform loading method is illustrated in Fig. 2. The minimum span between supports shall not be lessthan 2.5 multiplied by the aver
17、age depth of the specimen. Uniformly distributed transverse load shall be applied by air pressureusing an air bag over the full surface of the specimen. The air bag reaction frame shall fully contact one surface of the air bag andshall be sufficiently stiff as to not deflect more than the span divid
18、ed by 600 during testing.NOTE 3Air bags manufactured using 0.5 mm 0.02 in. thick polyvinyl chloride have been successfully used with this test. When testing specimensconstructed with a high bond-strength mortar, or whose thickness is greater than a nominal 100 mm 4 in., the applied load required to
19、fail the specimenmay be such as to rupture the seams of the air bag. In such cases Test Method A is recommended.6. Sampling and Testing6.1 Masonry UnitsRepresentative masonry units shall be sampled and tested in accordance with the following applicablemethods: Test Methods C67 for brick, or Test Met
20、hods C140 for concrete masonry units. Minimum tests required shall becompressive strength, and initial rate of absorption for brick or absorption for concrete masonry units.6.2 MortarOne of the types of mortar in Specification C270 shall be used, or the mortar shall conform to that specified forthe
21、construction. Sand sieve analysis shall be performed and recorded, except when ASTM C778 standard sand is used. If ASTMC778 standard sand is used, the record shall identify the sand as 2030 sand, graded sand, or a blend of indicated proportions ofeach sand by weight.6.2.1 Mortar for prism fabricatio
22、n shall be mixed to a workable consistency. The compressive strength, initial flow, and waterretention of the mortar shall be determined in accordance with the requirements of Specification C270, except that the cubesmolded for the compressive strength test, after moist curing in the molds for 24 h,
23、 shall be released and stored in the sameatmosphere as the prisms as specified in Section 78. The following physical properties of the mortar shall be determined andrecorded:6.2.2 Compressive strength (average of three cubes),6.2.3 Initial flow (laboratory-mixed mortar only),6.2.4 Flow after suction
24、 (water retention) (laboratory-mixed mortar only).7. Test Specimens7.1 A minimum of five test specimens shall be constructed as stack-bonded prisms, at least 460 mm 18 in. high with mortarjoints 10 6 1.5 mm 38 6 116 in. in thickness.The number of courses in each specimen shall be such as to permit l
25、ocating supportsand loading points midway between joints for Test MethodAtests (4, 7, 10, 13, or 16 courses, depending on face heights of units),and to provide for a span-to-depth ratio that exceeds 2.5. When the test is for the purpose of determining the quality of materialsand workmanship during c
26、onstruction, the specimens shall be constructed at the site by the masons involved, utilizing the materialson the site and the same masonry construction techniques.FIG. 1 The Third-Point Loading Method (Test Method A)E518/E518M 1527.2 Applicable portions of the following procedures shall be observed
27、:7.2.1 Set units on a firm, flat surface without the use of mortar, leaving not less than 50-mm 2-in. spaces between stretchers.7.2.2 Place a full or face shell mortar bed (in accordance with job specification) on all units without furrowing.7.2.3 Immediately place the next course of units on the mo
28、rtar bed and tap each unit to level. Align at least one vertical faceof each prism to a plane using a level or other means. (Note 4).7.2.4 Repeat steps 6.2.27.2.2 and 6.2.37.2.3 until the prisms are the required number of courses high. Tool or otherwise finishthe joints as specified.NOTE 4A convenie
29、nt method of aligning one face is to use a jig as illustrated in Fig. 3.8. Handling and Curing Conditions8.1 Unless otherwise specified, all prisms shall be cured for 28 days. The prisms together with corresponding mortar cubes shallbe cured in laboratory air maintained at a temperature of 24 6 8C 7
30、5 6 15F, with a relative humidity between 30 and 70 %,and free of drafts. These environmental conditions generally will not require special air-conditioning equipment. A continuousgraphical record of temperature and humidity will suffice to detect unusual dryness or excessive moisture, together with
31、 unusualfluctuations of temperature.8.1.1 Where prisms are made during construction at the job site, they shall be constructed in a place where they will not bedisturbed, but will be subjected to air conditions similar to those in the masonry structure.9. Procedure9.1 Place the test specimen horizon
32、tally on its supports as a simply supported beam. If full contact is not obtained between thespecimen and the load-applying blocks and supports, compressible shims or a bed of gypsum capping material shall be used tolevel and seat the specimen thereby ensuring the uniform application of load. If com
33、pressible shims are used, they shall be madeof leather or similar compressible material of uniform-thickness, not less than 6 mm 14 in. thick, 25 to 50 mm 1 to 2 in. in width,and shall extend across the full width of the specimen.9.2 Apply the load at a uniform rate of travel of the moving head such
34、 that the total load is applied in not less than 1 nor morethan 3 min.9.3 Record the maximum applied load in Newtons (pounds) as P and the location of the break.10. Calculation10.1 For specimens built with solid masonry units (75 % or more net area), calculate the gross area modulus of rupture asfol
35、lows (See Note 5):10.1.1 For Test Method A, with third-point loading:R 5P10.75 Ps!lbd2 (1)where:R = gross area modulus of rupture, MPa psi,P = maximum applied load indicated by the testing machine, N lbf,Ps = weight of specimen, N lbf,FIG. 2 The Uniform Loading Method (Test Method B)E518/E518M 153l
36、= span, mm in.,b = average width of specimen, mm in., andd = average depth of specimen, mm in.10.1.2 For Test Method B, with uniform loading:R 50.75 P1P s!lbd 2 (2)where the terms are the same as those described in 9.1.110.1.1.10.2 For specimens built with hollow masonry units (less than 75 % net ar
37、ea), calculate the net area modulus of rupture asfollows (See Note 5):10.2.1 For Test Method A, with third-point loading:R 50.167 P10.125 Ps!lS (3)where:S = section modulus of actual net bedded area, mm3 in. 3.10.2.2 For Test Method B, with uniform loading:R 50.125 P1P s!lS (4)where S is the same as
38、 in 9.2.110.2.1.NOTE 5The equations for determining the modulus of rupture values in 9.110.1 and 9.210.2 assume that the location of the failure plane occurs atFIG. 3 Use of a Jig to Align One Face of a Prism to a PlaneE518/E518M 154the mid-span of the specimen. Where the failure location is other t
39、han mid-span, the use of these equations for determining the modulus of rupture willnot be entirely accurate. Where a more precise assessment of the specimensmodulus of rupture values is deemed appropriate, a more thorough analysisusing accepted engineering mechanics should be employed.10.3 If the f
40、ailure occurs in a joint outside of the middle third of the span length for Method A, discard the test results.11. Report11.1 The report shall be prepared in conformance with Practice E575 and shall include the following:11.1.1 Identification number,11.1.2 Average width of specimen to the nearest 1.
41、0 mm 0.05 in.,11.1.3 Average depth of specimen to the nearest 1.0 mm 0.05 in.,11.1.4 Weight of specimen, N lbf,11.1.5 Method of applying load (Method A or B),11.1.6 Maximum applied load, N lbf,11.1.7 Individual and average gross or net area moduli of rupture calculated to the nearest MPa psi; standa
42、rd deviation; andcoefficient of variation.11.1.8 Curing history and age of specimen,11.1.9 Defects in specimen,11.1.10 Description of failure,11.1.11 Type and mix design of mortar,11.1.12 Compressive strength of mortar, kPa psi,11.1.13 Initial flow of mortar as used (laboratory-mixed mortar only),11
43、.1.14 Water retention of mortar (laboratory-mixed mortar only),11.1.15 Physical properties of masonry units, and11.1.16 Sketch or photograph of masonry unit showing core configuration and mortar bedded area, full or face shell.11.1.17 Results of the sand sieve analysis or, if ASTM C778 sand is used,
44、 identify which of the defined sands were used.12. Precision and Bias12.1 No statement is made either on the precision or on the bias of these test methods due to the variety of materials andcombinations of materials involved. Sufficient test data for all materials and combinations of materials are
45、not presently availableto permit the development of precision and bias statements.13. Keywords13.1 flexural bond strength; masonry units; mortar; simply supported beam; stack bonded prism; third point loading; uniformloadSUMMARY OF CHANGESCommittee C15 has identified the location of selected changes
46、 to this standard since the last issue(E518 09E518 10) that may impact the use of this standard. (Approved June (December 1, 2010.)2015)(1) Changes were incorporated intoAddedTerminology C1232 to 1.2Section 2and throughout the standard to permit the applicationof these test methods using either SI o
47、r inch-pound units(2) Clarifying revisions were incorporated into 4.2 and 4.3.(2) Fig. 1 andAdded Section Fig. 23 were modified to permit supporting spans greater than or equal to 2.5 multiplied by the depthof the specimen.to include a terminology reference.ASTM International takes no position respe
48、cting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This st
49、andard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved 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 that your comments have not received a fair hearing y
