【astm標(biāo)準(zhǔn)】c 1072 - 13e1

1、Designation: C1072 ? 13´1Standard Test Methods for Measurement of Masonry Flexural Bond Strength1This standard is issued under the fixed designation C1072; the number immediately following the designation indicates

2、the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (´) indicates an editorial change since the

3、last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.ε1 NOTE—Editorially corrected Table X1.1 in March 2014.1. Scope*1.1 These test methods evaluate the flexur

4、al bond strength, normal to the bed joints, of masonry built of manufactured masonry units. Sampling and testing procedures are referenced, and terms are defined. Three different specimen fabrication methods are specifie

5、d, each for a different purpose: 1.1.1 The first method is the “Test Method for Laboratory- Prepared Specimens.” Its purpose is to compare the bond strengths (under the given conditions) of masonry mortars. It could be u

6、sed, for example, to check the quality of mortar products after production, or to indicate the bond strength (under the given conditions) of a mortar product without requiring the product to be tested in combination with

7、 many different units. It is not intended to represent field conditions. It uses standard concrete masonry units. Mortars are batched by weight equivalents of volume proportions and are mixed to a prescribed flow. Prisms

8、 are constructed using a jig and are bag-cured. 1.1.2 The second method is the “Test Method for Field- Prepared Specimens.” Its purpose is to evaluate the bond strength (under the given conditions) of a particular unit-m

9、ortar combination, either for preconstruction evaluation of materials or for quality control purposes during construction. Mortars are batched conventionally, and the flow is not prescribed. Prisms are constructed conven

10、tionally (no jig) and are bag-cured. 1.1.3 The third method is the “Test Method for Prisms Removed from Existing Masonry.” Its purpose is to evaluate the bond strength of unit-mortar combinations of prisms cut from exist

11、ing walls. 1.1.4 The three methods are not consistent, nor are they intended to be. They are intended to be used for three different purposes. To make this clear, the three methods are presented separately. 1.1.5 Appendi

12、x X1 suggests two possible criteria for assess- ing the bond strength values obtained using these test methods.These possible evaluation criteria are given for illustration only and are not mandatory.1.2 The values state

13、d in inch-pound units are to be regarded as the standard. The values given in parentheses are mathemati- cal conversions to SI units that are provided for information only and are not considered standard.1.3 This standar

14、d does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro- priate safety and health practices and determine the ap

15、plica- bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C67 Test Methods for Sampling and Testing Brick and Structural Clay TileC140 Test Methods for Sampling and Testing Concrete

16、Masonry Units and Related UnitsC230/C230M Specification for Flow Table for Use in Tests of Hydraulic CementC270 Specification for Mortar for Unit Masonry C780 Test Method for Preconstruction and Construction Evaluation o

17、f Mortars for Plain and Reinforced Unit MasonryC1232 Terminology of Masonry C1437 Test Method for Flow of Hydraulic Cement Mortar C1532 Practice for Selection, Removal, and Shipment of Manufactured Masonry Units and Maso

18、nry Specimens from Existing Construction2.2 Other Documents: TMS 402 ?ACI 530 ?ASCE 5 Building Code Requirements for Masonry Structures31 These test methods are under the jurisdiction of ASTM Committee C15 on Manufacture

19、d Masonry Units and are the direct responsibility of Subcommittee C15.04 on Research. Current edition approved April 15, 2013. Published April 2013. Originally approved in 1993. Last previous edition approved in 2012 as

20、C1072 – 12. DOI: 10.1520/C1072-13E01.2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards volume information, refe

21、r to the standard’s Document Summary page on the ASTM website. 3 Available from the Masonry Standards Joint Committee, http:// www.masonrystandards.org.*A Summary of Changes section appears at the end of this standardCop

22、yright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1return the material used to measure flow to the mixer. If the flow is 127 6 3, continue mixing the bat

23、ch for an additional 2 min. If the flow is less than 124, add water to the batch, mix for 1 min, and determine flow. Once flow is recorded, return the material used to measure flow to the mixer. If the flow is 127 6 3, c

24、ontinue mixing the batch for 1 min. 9.1.2.2 If after the one-time addition of water the flow is not 127 6 3, discard the batch. 9.1.2.3 If the measured flow exceeds 130 at any time, discard the batch. 9.1.3 Immediately a

25、fter mixing the mortar, determine its initial cone penetration in accordance with Test Method C780. Determine the cone penetration of the mortar every 15 6 5 min. If the cone penetration is less than 80 % of its initial

26、value, discard the remaining portion of the mortar without constructing additional mortar joints. 9.1.4 Use standard concrete masonry units as defined inAnnex A1. Clean the bed surface of units of dirt, loose sand, or ot

27、her contaminants. 9.1.5 Fabricate prism specimens as described in Annex A2. 9.1.6 Cure prism specimens in accordance with Annex A2.9.2 Conduct bond-wrench tests on prism specimens. 9.2.1 Test the prisms in the same facil

28、ity where they were built. 9.2.2 Test masonry prisms in accordance with Annex A3. Determine the flexural tensile strength of each mortar joint tested, as described in Annex A3.NOTE 2—When test ages other than 28 days are

29、 specified, the general relationship between the strength at the specified test age and that at 28 days is generally established by test. That relationship may vary with different materials and curing conditions.10. Repo

30、rt10.1 Report the following information: 10.1.1 Identify mortar materials and units tested, including as applicable the manufacturer’s name, brand name, type, grade, source of sample, date sampled, and date tested. 10.1.

31、2 List unit and prism dimensions to the nearest 0.05 in. (1.0 mm), number of joints per prism, and number of prisms per set of specimens and prism weight. 10.1.3 Include the following in the report: 10.1.3.1 Weight of in

32、gredients (including water) added to the batch of mortar.10.1.3.2 Flow or cone penetrometer reading of mortar used to construct prisms. 10.1.3.3 Flexural bond strength test results for each joint of the test specimens. M

33、ean, standard deviation, and test age for each set of test specimens to the nearest psi. 10.1.3.4 If one or more mortar joints break during the handling of the specimen and tightening of the loading clamps but before add

34、itional load is applied by the testing apparatus, report which joints broke prematurely but do not include them in the calculation of the flexural tensile strength average and standard deviation. The top mortar joint sha

35、ll be designated joint Number 1, the second, Number 2, etc. Measured loads and calculations shall also be included. 10.1.3.5 Description of failure, especially indicating whether failure occurred at the top or bottom of

36、the mortar joint, or both.11. Precision and Bias11.1 Precision—Published data are not available for within- laboratory variability of this test method. Published data (Hedstrom,5 Melander6) obtained under conditions almo

37、st identical with those of this test method show within-batch coefficients of variation varying between 10 % and 25 % for 30-joint samples of selected portland cement-lime mortars and masonry cement mortars. Because only

38、 one sample of each mortar was tested in each laboratory, sufficient data are not available to establish repeatability for this test method. Inter- laboratory testing is now planned to determine the reproduc- ibility of

39、this test method. It is the intent of this committee to develop precision values within five years from the date of issuance of this test method.11.2 Bias—No information can be presented on the bias of this test method b

40、ecause no test having an accepted reference value is available.TEST METHOD FOR FIELD-PREPARED SPECIMENS12. Summary of Test Method12.1 This test method is for evaluating the flexural bond strength (under the given conditi

41、ons) of masonry built of conventional masonry units. Mortars are batched conventionally, and their flow is not prescribed. Prisms are constructed conventionally (no jig) and are bag-cured.13. Significance and Use13.1 Thi

42、s test method is intended for evaluation of flexural bond strength (under the given conditions) between mortar and units.13.2 The purpose of this test method is to evaluate the bond strength (under the given conditions)

43、of a particular unit-mortar combination, either for preconstruction evaluation of materials or for quality control purposes during construction. Precon- struction field tests may be used to provide information on the pot

44、ential performance of a mortar-unit combination under field conditions of fabrication and workmanship (but not curing). Construction field tests may be used as a quality control measure to ensure that performance criteri

45、a established in preconstruction tests are being met.5 Hedstrom, E. G., Tarhini, K. M., Thomas, R. D., Dubovoy, V. S., Klingner, R. E., and Cook, R. A., “Flexural Bond Strength of Concrete Masonry Prisms Using Portland C

46、ement and Hydrated Lime Mortars,” Masonry Society Journal, Vol 9 , No. 2, February 1991. 6 Melander, J. M., Ghosh, S. K., Dubovoy, V. S., Hedstrom, E. G., and Klingner, R. E., “Flexural Bond Strength of Concrete Masonry