ASTM_C_1042_-_99.pdf

Designation:C 1042 99Standard Test Method forBond Strength of Latex Systems Used With Concrete BySlant Shear1This standard is issued under the fixed designation C 1042;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 parentheses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of the bondstrength of latex bonding systems for use with portland-cementconcrete.This test method covers bonding hardened mortarspecimens to freshly mixed mortar specimens.1.2 The values stated in either inch-pound units or SI unitsare to be regarded separately as standard.Within the text,theSI units are shown in brackets.The values stated in eachsystem are not exact equivalents,therefore,each system shallbe used independently of the other.Combining values from thetwo systems may result in nonconformance with this testmethod.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of this standard to establish appropriate safetyand health practices and determine the applicability of regu-latory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:C 39 Test Method for Compressive Strength of CylindricalConcrete Specimens2C 109/C 109MTest Method for Compressive Strength ofHydraulic Cement Mortars(Using 2-in.or 50-mm CubeSpecimens)3C 150 Specification for Portland Cement3C 192 Practice for Making and Curing Concrete Test Speci-mens in the Laboratory2C 305 Practice for Mechanical Mixing of Hydraulic CementPastes and Mortars of Plastic Consistency3C 617 Practice for Capping Cylindrical Concrete Speci-mens2C 1059 Specification for LatexAgents for Bonding Fresh toHardened Concrete23.Summary of Test Method3.1 The bond strength is determined by using the latexsystem to bond a fresh mortar section of a 3 by 6 in.75 by 150mm portland-cement mortar cylinder to a hardened halfcylinder,that has a diagonally cast bonding area at an angle 30from vertical.After suitable curing of the composite specimen,the bond stress is determined by testing the specimen incompression and computing the bond strength at the diagonalface.4.Significance and Use4.1 This test method can be used in measuring the effec-tiveness of latex systems in bonding fresh concrete to hardenedconcrete.5.Apparatus5.1 Apparatus to Mix Portland-Cement MortarThis ap-paratus shall be as described in Practice C 305.5.2 Specimen MoldsThe molds shall be constructed in theform of right cylinders,3 6116in.75 6 2 mm in insidediameter and 6 6116in.150 6 2 mm high.All molds shallbe either selected or machined so that the maximum range ofthe differences in each of the dimensions of the group of moldsis less than164in.0.4 mm.The molds shall be made of metalnot attacked by portland-cement mortar.The side of the moldshall be sufficiently rigid to prevent spreading or warping.Themolds shall be made watertight before use.A satisfactorymaterial for this purpose is the paraffin-resin mixture describedin Test Method C 109/C 109M.5.3 Dummy SectionA dummy section(Fig.1)shall bemachined of a hard material that is not attacked by portland-cement mortar.It shall fit the mold and be equal to half thevolume of the cylinder,but at an angle 30 from vertical.Additional dummy sections can be made by casting an epoxyresin mortar against the machined dummy section contained ina specimen mold.Due precautions,such as waxing,shall betaken to prevent the bonding of the epoxy resin mortar to themachined dummy section or the mold.5.4 Tamping RodThe tamping rod shall be a round rod ofbrass or plastic,38in.10 mm in diameter and approximately12 in.300 mm long,having both ends rounded to hemispheri-cal tips.6.Half Cylinder Preparation6.1 Laboratory conditions,materials,proportions,and pro-cedures for mixing the portland-cement mortar shall be in1This test method is under the jurisdiction ofASTM Committee C-9 on Concreteand ConcreteAggregates and is the direct responsibility of Subcommittee C09.25 onOrganic Materials for Bonding.Current edition approved Feb.10,1999.Published May 1999.Originallypublished as C 1042 85.Last previous edition C 1042 91.2Annual Book of ASTM Standards,Vol 04.02.3Annual Book of ASTM Standards,Vol 04.01.1AMERICAN SOCIETY FOR TESTING AND MATERIALS100 Barr Harbor Dr.,West Conshohocken,PA 19428Reprinted from the Annual Book of ASTM Standards.Copyright ASTMaccordance with Test Method C 109/C 109M and the cementshall conform to Specification C 150,Type III.6.2 Lightly oil the dummy section and the cylinder mold.Position the dummy section in the mold with the slant side up.Place the portland-cement mortar in the mold in three layers ofapproximately equal volume.Rod each layer with 25 strokes ofthe tamping rod.Rod the bottom layer as deeply as possible.Distribute the strokes uniformly over the sect