1、Designation: E 518 03Standard Test Methods forFlexural Bond Strength of Masonry1This standard is issued under the fixed designation E 518; 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 paren
2、theses indicates the year of last reapproval. Asuperscript epsilon (e) 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 strength
3、 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 The values stated in SI units are to be regarded as thestandard.1.3 This standard does not purport to ad
4、dress 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 Documents2.1 ASTM Standards:C 67 Test Met
5、hods for Sampling and Testing Brick andStructural Clay Tile2C 78 Test Method for Flexural Strength of Concrete (UsingSimple Beam with Third-Point Loading)3C 140 Test Methods for Sampling and Testing ConcreteMasonry Units and Related Units2C 270 Specification for Mortar for Unit Masonry2C 778 Specifi
6、cation for Standard Sand4E 4 Practices for Force Verification of Testing Machines5E 72 Methods of Conducting Strength Tests of Panels forBuilding Construction6E 575 Practice for Reporting Data from Structural Tests ofBuilding Constructions, Elements, Connections, and As-semblies63. Significance and
7、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 or for the purpose of checking jobquality control (materials and workmanship).NOTE 1These te
8、st methods are not intended for use in establishingdesign stresses. For this purpose, Methods E 72 should be used.4. Apparatus4.1 Testing Machine, conforming to the requirements ofPractices E 4.4.2 Test Method AThe third-point loading method isillustrated in Fig. 1. The load is applied by means of a
9、 loadingapparatus similar to that described in Test Method C 78.4.3 Test Method BThe uniform loading method is illus-trated in Fig. 2. The load is applied by means of an air bagtypically made of poly(vinyl chloride) 0.5 mm (0.02 in.) thick.The air bag shall be of any convenient thickness and shall h
10、avea contact area equal to that of the specimen. It shall beequipped with two valves for inflating and deflating the bag.The air bag shall be backed by a steel channel suspended fromthe cross head of the testing machine with a suitable studwelded to the web of the channel. The channel shall be anAme
11、rican Standard steel channel whose depth is equal to thewidth of the air bag. It is recommended that the air pressure inthe bag be monitored during the test as a check against the testmachine dial indicator.NOTE 2When testing specimens constructed with a high bond-strength mortar, or whose thickness
12、 is greater than a nominal 100 mm (4in.), the applied load required to fail the specimen may be such as torupture the seams of the air bag. In such cases Test Method A isrecommended.5. Sampling and Testing5.1 Masonry UnitsRepresentative masonry units shall besampled and tested in accordance with the
13、 following applicablemethods: Test Methods C 67 for brick, or Test Methods C 140for concrete masonry units. Minimum tests required shall becompressive strength, and initial rate of absorption for brick orabsorption for concrete masonry units.1These test methods are under the jurisdiction of ASTM Com
14、mittee C15 onManufactured Masonry Units and are the direct responsibility of SubcommitteeC15.04 on Research.Current edition approved June 10, 2003. Published September 2003. Originallyapproved in 1974. Last previous edition approved in 2002 as E 51802.2Annual Book of ASTM Standards, Vol 04.05.3Annua
15、l Book of ASTM Standards, Vol 04.02.4Annual Book of ASTM Standards, Vol 04.01.5Annual Book of ASTM Standards, Vol 03.01.6Annual Book of ASTM Standards, Vol 04.11.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West
16、Conshohocken, PA 19428-2959, United States.5.2 MortarOne of the types of mortar in SpecificationC 270 shall be used, or the mortar shall conform to thatspecified for the construction. Sand sieve analysis shall beperformed and recorded, except when ASTM C 778 standardsand is used. If ASTM C 778 stand
17、ard sand is used, the recordshall identify the sand as 2030 sand, graded sand, or a blendof indicated proportions of each sand by weight.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 deter
18、mined inaccordance with the requirements of Specification C 270,except that the cubes molded for the compressive strength test,after moist 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
19、 mortar shallbe determined and recorded:5.2.2 Compressive strength (average of three cubes),5.2.3 Initial flow (laboratory-mixed mortar 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-bo
20、nded prisms, at least 460 mm (18 in.) high withmortar joints 10 6 1.5 mm (38 6116 in.) in thickness. Thenumber 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 height
21、s of units), and to provide 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
22、 masonry construction techniques.6.2 Applicable portions of the following procedures shall beobserved:FIG. 1 The Third-Point Loading Method (Test Method A)FIG. 2 The Uniform Loading Method (Test Method B)E5180326.2.1 Set units on a firm, flat surface without the use ofmortar, leaving not less than 5
23、0-mm (2-in.) spaces betweenstretchers.6.2.2 Place a full or face shell mortar bed (in accordancewith job specification) on all units 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 plan
24、e using a level or other means.(Note 3).6.2.4 Repeat steps 6.2.2 and 6.2.3 until the prisms are therequired number of courses high. Tool or otherwise finish thejoints as specified.NOTE 3A convenient method of aligning one face is to use a jig asillustrated in Fig. 3.7. Handling and Curing Conditions
25、7.1 Unless otherwise specified, all prisms shall be cured for28 days. The prisms together with corresponding mortar cubesshall be cured 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 conditionsg
26、enerally will not require special air-conditioning equipment.A continuous graphical record of temperature and humiditywill suffice to detect unusual dryness or excessive moisture,together with unusual fluctuations of temperature.7.1.1 Where prisms are made during construction at the jobsite, they sh
27、all be constructed in a place where they will not bedisturbed, but will be subjected to air conditions similar tothose in the masonry structure.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
28、load-applying blocks and supports,compressible shims or a bed of gypsum capping material shallbe 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
29、 less than 6 mm (14 in.) thick, 25 to 50mm (1 to 2 in.) in width, and 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 Ne
30、wtons (pounds)as P and the location of the break.FIG. 3 Use of a Jig to Align One Face of a Prism to a PlaneE5180339. Calculation9.1 For specimens built with solid masonry units (75 % ormore net area), calculate the gross area modulus of rupture asfollows:9.1.1 For Test Method A, with third-point lo
31、ading:R 5P 1 0.75 Ps!lbd2(1)where:R = gross area modulus of rupture, MPa (or psi),P = maximum applied load indicated by the testingmachine, N (or lbf),Ps= weight of specimen, N (or lbf),l = span, mm (or in.),b = average width of specimen, mm (or in.), andd = average depth of specimen, mm (or in.).9.
32、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 hollow masonry units (lessthan 75 % net area), calculate the net area modulus of ruptureas follows:9.2.1 For Test Method A, with third-point loading
33、:R 50.167 P 1 0.125 Ps!lS(3)where:S = section modulus of actual net bedded area, mm3(orin.3).9.2.2 For Test Method B, with uniform loading:R 50.125 P 1 Ps!lS(4)where S is the same as in 9.2.1.9.3 If the failure occurs in a joint outside of the middle thirdof the span length for Method A, discard the
34、 test results.10. Report10.1 The report shall be prepared in conformance withPractice E 575 and shall include the following:10.1.1 Identification number,10.1.2 Average width of specimen to the nearest 1.0 mm(0.05 in.),10.1.3 Average depth of specimen to the nearest 1.0 mm(0.05 in.),10.1.4 Weight of
35、specimen, N (or lbf),10.1.5 Method of applying load (Method A or B),10.1.6 Maximum applied load, N (or lbf),10.1.7 Individual and average gross or net area moduli ofrupture calculated to the nearest MPa (or psi); standarddeviation; and coefficient of variation.10.1.8 Curing history and age of specim
36、en,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 (or psi),10.1.13 Initial flow of mortar as used (laboratory-mixedmortar only),10.1.14 Water retention of mortar (laboratory-mixed mortaronly),10.1.15 Physica
37、l properties of masonry units, and10.1.16 Sketch of masonry unit showing core configurationand mortar bedded area, full or face shell.10.1.17 Results of the sand sieve analysis or, if ASTMC 778 sand is used, identify which of the defined sands wereused.11. Precision and Bias11.1 No statement is made
38、 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 and biasstatements.12. Keywords12.
39、1 flexural bond strength; masonry units; mortar; simplysupported beam; stack bonded prism; third point loading;uniform loadSUMMARY OF CHANGESCommittee C15 has identified the location of selected changes to the standard since the E 51802 version thatmay impact the use of this standard.(1) 6.2.3 was r
40、evised to clarify language regarding alignmentof test specimens.(2) 8.1 and Figure 3 were modified to allow other methods ofseating the specimen.(3) Figures 1 and 2 were changed to drawings, replacing theprevious photographs.E518034Committee C15 has identified the location of selected changes to the
41、 standard since the E 51800 version that may impact theuse of this standard.(1) Paragraph 6.2.5, which required dry-stacking units on topof the prisms to provide a surcharge load, was removed fromthe standard.(2) Paragraph 5.2 was revised to clarify and simplify therequired testing of the mortar. Sa
42、nd sieve analysis is waivedwhen a sand of known gradation is used.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 determination of the validity of any s
43、uch 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 or withdrawn. Your comments are invi
44、ted 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
45、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 reprints (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).E518035
