Designation: C1245/C1245M − 12Standard Test Method forDetermining Relative Bond Strength Between HardenedRoller Compacted Concrete Lifts (Point Load Test)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 (´) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method is intended for testing roller-compactedconcrete specimens and covers determination of the relativebond between layers of roller-compacted concrete or otherhardened concrete in multiple-lift forms of construction. It isapplicable to all types of layered roller-compacted concretewhere the total depth is sufficient to meet the minimumspecimen length and diameter requirements of this test method.This test method is not intended to provide tensile strengthresults of the material tested.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.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 consideredas requirements of this standard.1.4 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 applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C39/C39M Test Method for Compressive Strength of Cylin-drical Concrete SpecimensC42/C42M Test Method for Obtaining and Testing DrilledCores and Sawed Beams of ConcreteC125 Terminology Relating to Concrete and Concrete Ag-gregatesC192/C192M Practice for Making and Curing Concrete TestSpecimens in the LaboratoryC670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsC1176/C1176M Practice for Making Roller-CompactedConcrete in Cylinder Molds Using a Vibrating TableC1435/C1435M Practice for Molding Roller-CompactedConcrete in Cylinder Molds Using a Vibrating HammerD1557 Test Methods for Laboratory Compaction Character-istics of Soil Using Modified Effort (56,000 ft-lbf/ft3(2,700 kN-m/m3))3. Terminology3.1 Refer to Terminology C125 for definitions of terms usedin this test method.4. Significance and Use4.1 This test method is used to measure the relative bondstrength of roller-compacted concrete to other roller-compacted concrete by using a point load test at the joint (seeNote 1). Relative bond strength is determined using drilledcores or cast cylindrical specimens in which the bond surfaceis essentially normal to the longitudinal axis at approximatelythe mid-length of the specimen. A splitting tensile stressnormal to the bond surface is produced by applying a pointload at the joint.4.2 The test results in a value that can be compared to thatobtained by testing other specimens which are made from thesame materials and by the same process. Results can be usedfor the purpose of comparing the relative bond strength ofvarious joint conditions, joint treatments, or bonding materialsapplied to the joint.4.3 The test results are not to be taken as a true bondstrength. Values of cohesion or tensile strength shall bedetermined by methods other than this test method.4.4 This test method may be used either for laboratoryinvestigation by casting individual composite cylinders or bycoring prototype structures or assemblies (Test Method C42/C42M).NOTE 1—This test may be used for testing the relative bond of other1This test method is under the jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.45 on Roller-Compacted Concrete.Current edition approved April 1, 2012. Published May 2012. Originallyapproved in 1993. Last previous edition approved in 2011 as C1245/C1245M – 11.DOI: 10.1520/C1245_C1245M-12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at
[email protected] For Annual Book of ASTMStandards volume information, refer to the standard’s Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1hardened hydraulic cement-based materials other than RCC.5. Apparatus5.1 Testing Machine—The testing machine shall conform tothe requirements of Test Method C39/C39M.5.2 Testing Apparatus—The testing apparatus shall be con-structed of steel and allow the testing of both 100 and 150-mm[4 and 6-in.] diameter specimens. The test schematic is given inFig. 1. The testing apparatus shall permit the positioning of aspecimen such that the joint of the bonded surfaces is orientedas closely as possible parallel to the direction of loading. Figs.2-5 provide the information necessary to construct the appara-tus for 100 and 150-mm [4 and 6-in.] diameter specimens.Anvil rods (Fig. 2 and Fig. 3) shall have a hardness of not lessthan 55 HRC (Rockwell hardness number of 55 on the C scale)and shall be plane on the bearing surfaces to within 60.025mm [0.001 in.]. The alignment post shall ensure that the anvilrods are kept parallel to each other in the vertical plane. Thesystem is easily adaptable to most testing machines.6. Test Specimens6.1 Test specimens shall be cast cylinders or cores. Cylin-ders shall be cast in accordance with Practice C1176/C1176M,Practice C1435/C1435M, or Test Method D1557 and be 100 or150 mm [4 or 6 in.] in diameter. Cores shall be obtained inaccordance with Practice C42/C42M and be 100 or 150 mm [4or 6 in] in diameter. Cut specimen to ensure that the plane bestdescribing the bond surface is oriented at 90 6 15° to the longaxes of the specimens.6.2 Cure molded test specimens in accordance with PracticeC192/C192M (laboratory specimens). Drilled cores shall bemoisture conditioned in accordance with Test Method C42/C42M.NOTE 2—Test results are not affected significantly by specimen surfacesFIG. 1 Schematic of Loading MethodC1245/C1245M − 122obtained with normal coring operations. The ends of cores need not betrimmed.NOTE 3—Where the bond surface undulates grossly, that is, the surfacehas a local texture exceeding 15 mm [0.5 in.] in amplitude, 150-mm [6-in.]diameter cores are preferable. No information is available on the relativeresults of 150-mm [6-in.] versus 100-mm [4-in.] diameter specimens.7. Procedure7.1 Measurements—Determine the diameter of the testspecimens by averaging three diameters measured on the bondsurface. Visually identify the bond surface by color, texture, orNOTE 1—Dimensions are shown in mm, refer to Table 1 for values ininches.NOTE 2—x =~L275!2, where L is the length of the anvil rod ordiameter of the top plate.FIG. 2 Top Plate and Anvil RodC1245/C1245M − 123material contrasts. Measure diameters 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 lengthsto determine the section length-to-diameter ratios. Specimensmust have a minimum length-to-diameter ratio of 1.2 if thebond plane is at mid-length (within 65 mm [0.25 in.]) of thespecimen. If the bond plane is not at mid-length of thespecimen, the section on each side of the bond plane shall beNOTE 1—Dimensions are shown in mm, refer to Table 1 for values ininches.FIG. 3 Base Plate and Anvil RodC1245/C1245M − 124of a length at least 0.6 the diameter. Where the bond surface isirregular or undulating, mark on the specimen a line represent-ing a plane extending through and along the approximateaverage bearing of the bond surface, and measure the lengthfrom this line.7.2 Positioning—Assemble and position the apparatus in thetesting machine. Place the specimen on the bottom plate withthe joint in contact with the anvil rods (see Fig. 1). The longeranvil 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 anvil rods (Fig. 2 and Fig. 3) and the shorteralignment post (Fig. 4) are used to test 100-mm [4-in.]diameter specimens.7.2.1 Zero the load-indicating mechanism. Position thespecimen so that the bond surface is parallel to the upper andlower anvil rods (see Fig. 1). This is best accomplished bypositioning the specimen by hand while gently bringing the topanvil into contact with the specimen. Alternatively, the speci-men may be supported with modeling clay or pieces ofpolystyrene. Where the bond surface is irregular or undulating,align the anvil rods along the approximate average bearing ofthe bond surface. Bring the anvil rods in contact with the bondsurface at the contact point on the circumference of thespecimen.7.3 Loading—Do not preload the specimen. Apply the loadat a uniform rate within the range of 1 to 1.4 MPa/min [150 to200 psi/min] until the specimen fails. Record the maximumload applied.8. Calculation8.1 Calculate the relative bond strength as follows:ftb5PD2NOTE 1—Dimensions are shown in mm, refer to Table 1 for values ininches.FIG. 4 Alignment Post for 100 mm [4 in] Diameter SpecimensC1245/C1245M − 125where:ftb= relative bond strength, MPa [psi],P = maximum applied load, N [lbf], andD = average specimen diameter at bond surface, mm [in.].9. Report9.1 Report the following information:9.1.1 Date of testing.9.1.2 Specimen identification and if cored, the location ofthe 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 fabrication including the practice or testmethod used to cast or mold cylinders;9.1.3.3 Details of bonding techniques;9.1.3.4 Age, when tested;9.1.3.5 Specimen size including diameter and length of eachlayer material and whether a cast cylinder or drilled core wasused; and9.1.3.6 Any other information necessary to describe theproduction or features of the specimens.9.1.4 Record of curing and moisture condition of the speci-mens at the time of test.9.1.5 Any special treatment or prior testing performed onthe specimens.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 the fracture occur along the original bondsurface, the nature of the surface such as texture (smooth orrough), appearance (glossy or dull, undulating or flat), anddetailed descriptions of discoloration, foreign objects ormaterials, loose or dusty material in voids, and the suspectedpresence and condition, or absence, of any bonding improve-ment agent;9.1.7.3 Alternatively, should the plane of fracture occurpartially or totally within the concrete layers adjacent to thebond surface, the percentage of the total area subjected to thisNOTE 1—Dimensions are shown in mm, refer to Table 1 for values ininches.FIG. 5 Alignment Post for 150 mm [6 in] Diameter SpecimensC1245/C1245M − 126type of failure versus the percentage area where failureoccurred at the bond surface; and9.1.7.4 Any unexpected features.10. Precision and Bias10.1 Precision—Precision of this test method was calculatedfrom results published in Saucier,3which compared bondstrength of bonded and unbonded concrete for five mixtures ofvarying proportions. These data only represent within labora-tory data for a single laboratory. A report of this analysis is onfile at ASTM International Headquarters, as Research ReportRR:C09-1025.410.1.1 The single-laboratory single-batch standard devia-tion for relative bond strength of unbonded concrete cores hasbeen found to be 0.16 MPa [23 psi].5Therefore, results of testson two cores taken from the same batch of concrete are notexpected to differ more than 0.44 MPa [64 psi].510.1.2 The single-laboratory single-batch standard devia-tion for relative bond strength of cores 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 ofconcrete are not expected to differ more than 0.73 MPa [106psi].510.2 Bias—This test method has no bias because there is nostandard material on which to estimate this property.11. Keywords11.1 bond strength; bonding agents; concrete bonding;roller-compacted concretesSUMMARY OF CHANGESCommittee C09 has identified the location of selected changes to this test method since the last issue,C1245/C1245M – 11, that may impact the use of this test method. (Approved April 1, 2012.)(1) The word “relative” was added to the title and to severallocations throughout the standard to emphasize that the testresults are in “relative bond strength” as opposed to true bondstrength.(2) “Other hardened cementitious mixtures” was deleted fromthe title and from the Significance and Use section to clarifythat the purpose of the test is for testing relative bond betweenlayers of RCC. Statements were added to the Significance andUse section to emphasize that the values of true bond strengthare not obtained by this test method and that values of tensilestrength and cohesion shall be obtained by methods other thanthis test method.(3) A note was added to the Significance and Use sectionstating the test may be used for testing the relative bond ofhardened hydraulic cement-based materials other than RCC.Committee C09 has identified the location of selected changes to this test method since the last issue,C1245/C1245M – 06, that may impact the use of this test method. (Approved April 1, 2011.)(1) Reordered all units so that SI units appear first.(2) Replaced old Figures 2–9 with new Figs. 2-5.(3) Replaced old Table 1 with new Table 1 showing rational-ized units with SI units listed first.3Saucier, K. L. “No-Slump Roller Compacted Concrete (RCC) for Use in MassConcrete 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 maybe obtained by requesting Research Report RR:C09-1025. ContactASTM CustomerService at
[email protected] numbers represent, respectively, the (ls) and (d2s) limits as described inPractice C670.TABLE 1 Inch-Pound Equivalents for Figs. 2-5mm in.1 0.0392 0.0794 0.1576 0.2368 0.31511 0.43313 0.51214 0.55115 0.59116 0.63017 0.66925 0.98429 1.14240 1.57545 1.77265 2.55970 2.75675 2.95390 3.54395 3.740100 3.937115 4.528120 4.724130 5.118140 5.512145 5.709150 5.906165 6.496C1245/C1245M − 127ASTM International takes no position respecting the validity of any paten
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