ASTM C1245 C1245M-2012 Standard Test Method for Determining Relative Bond Strength Between Hardened Roller Compacted Concrete Lifts (Point Load Test)《测定硬化碾压混凝土和其他硬化粘结混合物间粘合强度的标准试验方.pdf

《ASTM C1245 C1245M-2012 Standard Test Method for Determining Relative Bond Strength Between Hardened Roller Compacted Concrete Lifts (Point Load Test)《测定硬化碾压混凝土和其他硬化粘结混合物间粘合强度的标准试验方.pdf》由会员分享，可在线阅读，更多相关《ASTM C1245 C1245M-2012 Standard Test Method for Determining Relative Bond Strength Between Hardened Roller Compacted Concrete Lifts (Point Load Test)《测定硬化碾压混凝土和其他硬化粘结混合物间粘合强度的标准试验方.pdf（8页珍藏版）》请在麦多课文档分享上搜索。

1、Designation:C1245/C1245M11 Designation: C1245/C1245M 12Standard Test Method forDetermining Bond Strength Between Hardened RollerCompacted Concrete and Other Hardened CementitiousMixtures (Point Load Test)Determining Relative BondStrength Between Hardened Roller Compacted ConcreteLifts (Point Load Te

2、st)1This standard is issued under the fixed designation C1245/C1245M; the number immediately following the designation indicates theyear of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon ()

3、 indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method is intended for testing roller-compacted concrete specimens and covers determination of the relative bondbetween layers of roller-compacted concrete or other hardened concrete in multiple-lift forms of

4、 construction. It is applicable toall types of layered roller-compacted concrete where the total depth is sufficient to meet the minimum specimen length anddiameter requirements of this test method. This test method is not intended to provide tensile strength results of the material tested.1.2 The v

5、alues stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from thetwo systems may result in non-conformance with the st

6、andard.1.3 The text of this standard references notes and footnotes, which provide explanatory material. These notes and footnotes(excluding those in tables and figures) shall not be considered as requirements of this standard.1.4 This standard does not purport to address all of the safety concerns,

7、 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 Documents2.1 ASTM Standards:2C39/C39M Test Method for Compressive Strength o

8、f Cylindrical Concrete SpecimensC42/C42M Test Method for Obtaining and Testing Drilled Cores and Sawed Beams of ConcreteC125 Terminology Relating to Concrete and Concrete AggregatesC192/C192M Practice for Making and Curing Concrete Test Specimens in the LaboratoryC670 Practice for Preparing Precisio

9、n and Bias Statements for Test Methods for Construction MaterialsC1176/C1176M Practice for Making Roller-Compacted Concrete in Cylinder Molds Using a Vibrating TableC1435/C1435M Practice for Molding Roller-Compacted Concrete in Cylinder Molds Using a Vibrating HammerD1557 Test Methods for Laboratory

10、 Compaction Characteristics of Soil Using Modified Effort (56,000 ft-lbf/ft3(2,700kN-m/m3)3. Terminology3.1 Refer to Terminology C125 for definitions of terms used in this test method.4. Significance and Use4.1This test method is used to measure the effectiveness of bonding roller-compacted concrete

11、 to other roller-compactedconcrete or other hardened cementitious mixtures by using a point load test at the joint. Bond strength is determined using drilledcores or cast cylindrical specimens in which the bond surface is essentially normal to the longitudinal axis at approximately themid-length of

12、the specimen. A splitting tensile stress normal to the bond surface is produced by applying a point load at the joint.1This test method is under the jurisdiction of ASTM Committee C09 on Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee C09.45 onRoller-Compacted Concr

13、ete.Current edition approved April 1, 2011.2012. Published May 2011.2012. Originally approved in 1993. Last previous edition approved in 20062011 as C1245/C1245M06.C1245/C1245M11. DOI: 10.1520/C1245_C1245M-112.2For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Cust

14、omer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.1This 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 t

15、he previous version. Becauseit may not be technically possible to adequately 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

16、 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.4.2This test method may be used either for laboratory investigation by casting individual composite cylinders or by coringprototyp

17、e structures or assemblies (Test Method4.1 This test method is used to measure the relative bond strength of roller-compacted concrete to other roller-compactedconcrete by using a point load test at the joint (See Note 1). Relative bond strength is determined using drilled cores or castcylindrical s

18、pecimens in which the bond surface is essentially normal to the longitudinal axis at approximately the mid-length ofthe specimen. A splitting tensile stress normal to the bond surface is produced by applying a point load at the joint.4.2 The test results in a value that can be compared to that obtai

19、ned by testing other specimens which are made from the samematerials and by the same process. Results can be used for the purpose of comparing the relative bond strength of various jointconditions, joint treatments, or bonding materials applied to the joint.4.3 The test results are not to be taken a

20、s a true bond strength. Values of cohesion or tensile strength shall be determined bymethods other than this test method.4.4 This test method may be used either for laboratory investigation by casting individual composite cylinders or by coringprototype structures or assemblies (Test Method C42/C42M

21、). ).NOTE 1This test may be used for testing the relative bond of other hardened hydraulic cement-based materials other than RCC.5. Apparatus5.1 Testing MachineThe testing machine shall conform to the requirements of Test Method C39/C39M.5.2 Testing ApparatusThe testing apparatus shall be constructe

22、d of steel and allow the testing of both 100 and 150-mm 4 and6-in. diameter specimens. The test schematic is given in Fig. 1. The testing apparatus shall permit the positioning of a specimensuch that the joint of the bonded surfaces is oriented as closely as possible parallel to the direction of loa

23、ding. Figs. 2-5 providethe information necessary to construct the apparatus for 100 and 150-mm 4 and 6-in. diameter specimens. Anvil rods (Fig. 2 andFig. 3) shall have a hardness of not less than 55 HRC (Rockwell hardness number of 55 on the C scale) and shall be plane on thebearing surfaces to with

24、in 60.025 mm 0.001 in. The alignment post shall ensure that the anvil rods are kept parallel to each otherin the vertical plane. The system is easily adaptable to most testing machines.6. Test Specimens6.1 Test specimens shall be cast cylinders or cores. Cylinders shall be cast in accordance with Pr

25、actice C1176/C1176M, PracticeC1435/C1435M, or Test Method D1557 and be 100 or 150 mm 4 or 6 in. in diameter. Cores shall be obtained in accordance withPractice C42/C42M and be 100 or 150 mm 4 or 6 in in diameter. Cut specimen to ensure that the plane best describing the bondsurface is oriented at 90

26、 6 15 to the long axes of the specimens.6.2 Cure molded test specimens in accordance with Practice C192/C192M (laboratory specimens). Drilled cores shall bemoisture conditioned in accordance with Test Method C42/C42M.NOTE1Test 2Test results are not affected significantly by specimen surfaces obtaine

27、d with normal coring operations. The ends of cores need notbe trimmed.NOTE2Where 3Where the bond surface undulates grossly, that is, the surface has a local texture exceeding 15 mm 0.5 in. in amplitude, 150-mm6-in. diameter cores are preferable. No information is available on the relative results of

28、 150-mm 6-in. versus 100-mm 4-in. diameter specimens.7. Procedure7.1 MeasurementsDetermine the diameter of the test specimens by averaging three diameters measured on the bond surface.Visually identify the bond surface by color, texture, or material contrasts. Measure diameters to the nearest 0.25 m

29、m 0.01 in. withcalipers, whenever possible, but at least to the nearest 2.5 mm 0.1 in. Determine the length of each section of the bondedspecimens to the nearest 2.5 mm 0.1 in., and use these lengths to determine the section length-to-diameter ratios. Specimens musthave a minimum length-to-diameter

30、ratio of 1.2 if the bond plane is at mid-length (within 65 mm 0.25 in.) of the specimen. Ifthe bond plane is not at mid-length of the specimen, the section on each side of the bond plane shall be of a length at least 0.6the diameter. Where the bond surface is irregular or undulating, mark on the spe

31、cimen a line representing a plane extending throughand along the approximate average bearing of the bond surface, and measure the length from this line.NOTE3Many drilled cores will not be smooth enough to justify the measurement of diameters closer than to the nearest 2.5 mm 0.1 in.7.2 PositioningAs

32、semble and position the apparatus in the testing machine. Place the specimen on the bottom plate with thejoint in contact with the anvil rods (see Fig. 1). The longer anvil rods (Fig. 2 and Fig. 3) and the longer alignment post (Fig. 5)are used to test 150-mm 6-in. diameter specimens. The shorter an

33、vil rods (Fig. 2 and Fig. 3) and the shorter alignment post (Fig.4) are used to test 100-mm 4-in. diameter specimens.7.2.1 Zero the load-indicating mechanism. Position the specimen so that the bond surface is parallel to the upper and lower anvilrods (see Fig. 1). This is best accomplished by positi

34、oning the specimen by hand while gently bringing the top anvil into contactwith the specimen. Alternatively, the specimen may be supported with modeling clay or pieces of polystyrene. Where the bondsurface is irregular or undulating, align the anvil rods along the approximate average bearing of the

35、bond surface. Bring the anvilrods in contact with the bond surface at the contact point on the circumference of the specimen.7.3 LoadingDo not preload the specimen. Apply the load at a uniform rate within the range of 1 to 1.4 MPa/min 150 to 200psi/min until the specimen fails. Record the maximum lo

36、ad applied.C1245/C1245M 1228. Calculation8.1Calculate the strength of the bond as follows:8.1 Calculate the relative bond strength as follows:ftb5PD2C1245_C1245M-12_1where:ftb= relative bond strength, MPa psi,P = maximum applied load, N lbf, andD = average specimen diameter at bond surface, mm in.9.

37、 Report9.1 Report the following information:9.1.1 Date of testing.9.1.2 Specimen identification and if cored, the location of the core.9.1.3 Details of the materials comprising the specimens, such as the following:9.1.3.1 Mixture proportions of the concretes and mortars;9.1.3.2 Details of fabricatio

38、n including the practice or test method used to cast or mold cylinders;FIG. 1 Schematic of Loading MethodC1245/C1245M 1239.1.3.3 Details of bonding techniques;NOTE 1Dimensions are shown in mm, refer to Table 1 for values ininches.Note 2 x 5L275!2, where L is the length of the anvil rod ordiameter of

39、 the top plate.FIG. 2 TNOP PTEx =L275!2, where L is the laength of the and Anvil R rodor diameter of the top plate.FIG. 2 Top Plate and Anvil RodC1245/C1245M 1249.1.3.4 Age, when tested;9.1.3.5 Specimen size including diameter and length of each layer material and whether a cast cylinder or drilled

40、core was used;and9.1.3.6 Any other information necessary to describe the production or features of the specimens.NOTEDimensions are shown in mm, refer to Table 1 for values ininches.FIG. 3 Base Plate and Anvil RodC1245/C1245M 1259.1.4 Record of curing and moisture condition of the specimens at the t

41、ime of test.9.1.5 Any special treatment or prior testing performed on the specimens.9.1.6Strength of the 9.1.6 Relative bond strength to the nearest 0.1 MPa 10 psi.9.1.7 Mode of failure:9.1.7.1 Whether bond failure or aggregate failure, or both, were observed in the plane of failure;9.1.7.2 Should t

42、he fracture occur along the original bond surface, the nature of the surface such as texture (smooth or rough),appearance (glossy or dull, undulating or flat), and detailed descriptions of discoloration, foreign objects or materials, loose ordusty material in voids, and the suspected presence and co

43、ndition, or absence, of any bonding improvement agent;9.1.7.3 Alternatively, should the plane of fracture occur partially or totally within the concrete layers adjacent to the bondsurface, the percentage of the total area subjected to this type of failure versus the percentage area where failure occ

44、urred at thebond surface; and9.1.7.4 Any unexpected features.NOTEDimensions are shown in mm, refer to Table 1 for values ininches.FIG. 4 Alignment Post for 100 mm 4 in Diameter SpecimensC1245/C1245M 12610. Precision and Bias10.1 PrecisionPrecision of this test method was calculated from results publ

45、ished in Saucier,3which compared tensilebondstrength of bondsbonded and unbonded concrete for five mixtures of varying proportions. These data only represent withinlaboratory data for a single laboratory. A report of this analysis is on file at ASTM International Headquarters, as Research ReportRR:C

46、09-1025.410.1.1 The single-laboratory single-batch standard deviation for splitting tensilerelative bond strength of unbonded concretecores has been found to be 0.16 MPa 23 psi.5in 95% of the cases. Therefore, results of tests on two cores taken from the samebatch of concrete should differ by no mor

47、e than 0.44 MPa 64 psi5in 95% of cases.10.1.2The single-laboratory single-batch standard deviation for splitting tensile bond strength of cores obtained from a layeredspecimen has been found to be 0.26 MPa 38 psi5in 95% of the cases. Therefore, results of tests on two cores taken from thesame batch

48、of concrete should differ by no more than 0.73 MPa 106 psi in 95% of cases. Therefore, results of tests on two corestaken from the same batch of concrete are not expected to differ more than 0.44 MPa 64 psi.510.1.2 The single-laboratory single-batch standard deviation for relative bond strength of c

49、ores obtained from a layeredspecimen has been found to be 0.26 MPa 38 psi.5Therefore, results of tests on two cores taken from the same batch of concrete3Saucier, K. L. “No-Slump Roller Compacted Concrete (RCC) for Use in Mass Concrete Construction,” Technical Report SL-84-17, U.S. Army Research andDevelopment Center, 3909 Halls Ferry Rd., Vicksburg, MS 39180, 1984.4Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:C09-1025.5