ASTM G109-2007(2013) Standard Test Method for Determining Effects of Chemical Admixtures on Corrosion of Embedded Steel Reinforcement in Concrete Exposed to Chloride Environments《测.pdf

1、Designation: G109 07 (Reapproved 2013)Standard Test Method forDetermining Effects of Chemical Admixtures on Corrosionof Embedded Steel Reinforcement in Concrete Exposed toChloride Environments1This standard is issued under the fixed designation G109; the number immediately following the designation

2、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 () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers a procedure fo

3、r determining theeffects of chemical admixtures on the corrosion of metals inconcrete. This test method can be used to evaluate materialsintended to inhibit chloride-induced corrosion of steel inconcrete. It can also be used to evaluate the corrosivity ofadmixtures in a chloride environment.1.2 The

4、values stated in SI units are to be regarded asstandard. The values given in parentheses are for informationonly.1.3 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 sa

5、fety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2A615/A615M Specification for Deformed and Plain Carbon-Steel Bars for Concrete ReinforcementC33 Specification for Concrete AggregatesC143/C143M Test Method for

6、 Slump of Hydraulic-CementConcreteC150 Specification for Portland CementC173/C173M Test Method forAir Content of Freshly MixedConcrete by the Volumetric MethodC192/C192M Practice for Making and Curing Concrete TestSpecimens in the LaboratoryC231 Test Method for Air Content of Freshly Mixed Con-crete

7、 by the Pressure MethodC511 Specification for Mixing Rooms, Moist Cabinets,Moist Rooms, and Water Storage Tanks Used in theTesting of Hydraulic Cements and ConcretesC876 Test Method for Corrosion Potentials of UncoatedReinforcing Steel in ConcreteC881/C881M Specification for Epoxy-Resin-Base Bonding

8、Systems for ConcreteC1152/C1152M Test Method for Acid-Soluble Chloride inMortar and ConcreteD448 Classification for Sizes of Aggregate for Road andBridge ConstructionD632 Specification for Sodium ChlorideE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Condu

9、cting an Interlaboratory Study toDetermine the Precision of a Test MethodG3 Practice for Conventions Applicable to ElectrochemicalMeasurements in Corrosion TestingG15 Terminology Relating to Corrosion and Corrosion Test-ing (Withdrawn 2010)3G33 Practice for Recording Data from Atmospheric Corro-sion

10、 Tests of Metallic-Coated Steel SpecimensG46 Guide for Examination and Evaluation of Pitting Cor-rosion2.2 NACE Standards:4SSPC-SP 5/NACE No. 1 White Metal Blast Cleaning3. Significance and Use3.1 This test method provides a reliable means for predict-ing the inhibiting or corrosive properties of ad

11、mixtures to beused in concrete.3.2 This test method is useful for development studies ofcorrosion inhibitors to be used in concrete.3.3 This test method has been used elsewhere with goodagreement between corrosion as measured by this test method1This test method is under the jurisdiction of ASTM Com

12、mittee G01 onCorrosion of Metals and is the direct responsibility of Subcommittee G01.14 onCorrosion of Metals in Construction Materials.Current edition approved May 1, 2013. Published July 2013. Originally approvedin 1992. Last previous edition approved in 2007 as G10907. DOI: 10.1520/G0109-07R13.2

13、For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is refe

14、renced onwww.astm.org.4Available from The Society for Protective Coatings (SSPC), 40 24th St., 6thFloor, Pittsburgh, PA 15222-4656.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1and corrosion damage on the embedded steel (1-4).5This

15、testmethod might not properly rank the performance of differentcorrosion inhibitors, especially at concrete covers over the steelless than 40 mm (1.5 in.) or water-to-cement ratios above 0.45.The concrete mixture proportions and cover over the steel arechosen to accelerate chloride ingress. Some inh

16、ibitors mighthave an effect on this process, which could lead to results thatwould differ from what would be expected in actual use (5).4. Apparatus4.1 The apparatus required for the evaluation of corrosioninhibitors includes a high impedance voltmeter (at least oneMohm) capable of measuring to 0.01

17、 mV, a 100 (65%)resistor.5. Reagents and Materials5.1 Cement, that conforms to Type I or Type II of Specifi-cation C150. Coarse aggregate shall conform to SpecificationC33 and Classification D448, with nominal maximum sizebetween 9.5 and 19 mm (38 and34 in.).NOTE 1Preferred maximum size aggregate is

18、 12.5 mm (0.5 in.).5.2 Steel Reinforcement Bars, deformed, meeting the re-quirement of Specification A615/A615M; with a diameterbetween 10 mm (0.4 in.) and 16 mm (0.6 in.), and a length of360 mm (14 in.), drilled and tapped at one end to be fitted withcoarse-thread stainless steel and nuts, as descr

19、ibed in 5.3 and5.4.These bars shall be used to manufacture the test specimens,as described in Section 6.NOTE 2Interlaboratory test program and statistical data in Section 11are based upon 13-mm (0.5-in.) steel bars, 12.5-mm maximum sizeaggregate, and 19-mm (0.75-in.) and 25-mm (1 in.) cover.5.3 316

20、Stainless Steel Screws, with diameter smaller thanbar diameter (coarse thread5mm(0.2 in.), 25 to 35-mm (1to 1.5-in.) long (one per bar).5.4 316 Stainless Steel Nuts, two per bar to fit stainless steelscrews, as described in 5.3.5.5 Two-part Waterproof Epoxy6,7This epoxy shall meetthe chemical resist

21、ance requirements of a Type IV, Grade 3,Class E of Specification C881/C881M.5.6 Sulfuric Acid, 10 % by mass, for pickling (optional).5.7 Electroplaters Tape.7,85.8 Neoprene Tubing, with 3-mm (18-in.) wall thickness andthe same ID as the diameter of the bar used.5.9 Sodium Chloride, complying with Sp

22、ecification D632.5.10 Salt Solution, prepared by dissolving 3 parts of sodiumchloride (as described in 5.9) in 97 parts of water mass.5.11 Epoxy Sealer, for application to the concrete specimensafter manufacture. This sealer shall be of Type III, Grade 1,Class C in accordance with Specification C881

23、/C881M.7,95.12 Plastic Dams, 75-mm (3-in.) wide and 150-mm (6-in.)long with a minimum height of 75 mm (3 in.) for placement onthe test specimens. The wall thickness shall be 61mm(18 6132 in.5.13 Silicone Caulk, for sealing the outside of the plasticdam to the top of the concrete specimen.7,105.14 Re

24、ference Electrode, such as a saturated calomel orsilver/silver chloride electrode for measuring the corrosionpotential of the bars, as defined in Terminology G15.5.15 Hexane.6. Preparation of Test Specimens6.1 Power wire brush or sand blast the bars to near whitemetal (see SSPC-SP 5/NACE No. 1), cle

25、an by soaking inhexane, and allow to air dry.NOTE 3Pickling the bars with 10 % sulfuric acid for 10 to 15 min andrinsing with potable water prior to wire brushing is recommended whenthe bars have an excessive amount of rust.6.2 Use the same method to clean all bars in the testprogram.6.3 Drill and t

26、ap one end of each bar, attach a stainless steelscrew and two nuts, as described in 5.3 and 5.4, and tape eachend of the bar with electroplaters tape so that a 200-mm (8-in.)portion in the middle of the bar is bare. Place a 90-mm (3.5 in.)length of neoprene tubing, as described in 5.8, over theelect

27、roplaters tape at each end of the bar, and fill the length oftubing protruding from the bar ends with the two-part epoxy, asdescribed in 5.5.6.4 Specimen size is 280 150 115 mm (1164.5in.).Place two bars, as described in 5.2, 25 mm (1 in.) from thebottom, and one bar at the top such that the distanc

28、e from itstop to the top surface of the specimen is twice the maximumaggregate size, as shown in Fig. 1.NOTE 4For example, for a 12.5-mm (0.5 in.) aggregate, place the topbar 25 mm (1 in.) from the surface. For a 9.5-mm (0.375-in.) aggregate,place the bar 19 mm (0.75 in.) from the top surface.6.5 Pl

29、ace the bars in the molds so that 40 mm (approxi-mately 1.5 in.) of the bars are protected within each exit endfrom the concrete (minimizes edge effects). This will expose200 mm (8 in.) of steel. Place the bars with the longitudinal ribsso that they are nearer the side of the beam, that is, both rid

30、gesare equidistant from the top or bottom of the specimen.6.6 Make the concrete specimens (controls and those withadmixtures to be tested) in accordance with Practice C192/C192M, using the same source of materials. Determine the aircontent, using either Test Method C231 or C173/C173M. Thewater-to-ce

31、ment ratio (w/c) shall not exceed 0.5. The minimum5The boldface numbers in parentheses refer to a list of references at the end ofthis standard.6The sole source of supply of the apparatus known to the committee at this timeis PC-Epoxy, made by Protective Coating Co., Allentown, PA.7If you are aware

32、of alternative suppliers, please provide this information toASTM International Headquarters. Your comments will receive careful consider-ation at a meeting of the responsible technical committee,1which you may attend.8The sole source of supply of the apparatus known to the committee at this timeis M

33、innesota Mining and Manufacturing Company (3M), 1999 Mt. Read Boulevard,Rochester, NY 14615.9The sole source of supply of the apparatus known to the committee at this timeis Epoxy Concrete Scaler # 12560, made by Devcon.10The sole source of supply of the apparatus known to the committee at this time

34、is 3M Marine Adhesive 5200.G109 07 (2013)2slump is 50 mm (2 in.) (See Test Method C143/C143M). Placeand consolidate the concrete in the molds containing the bars inaccordance with Practice C192/C192M.NOTE 5The concrete parameters used in the interlaboratory test wereas follows: cement content of 355

35、 6 3 kg/m3(600 6 5 lb/yd3), 0.50 60.01 w/c (ssd aggregates), and 6 6 1 % air.6.7 Add the admixture to be tested at the manufacturersrecommended dosages. A water reducer is allowed, if needed,to achieve the desired slump. Record the admixtures used.Except for the test admixtures, use the same admixtu

36、res in allmixtures.6.8 A minimum of three replicates shall be made. Make thesame number of replicates per admixture tested and control(see Note 6). An addition cylinder 100 200 mm (4 8 in.) indiameter shall be produced for background chloride analysis.NOTE 6A larger number of replicates is preferred

37、.6.9 Apply a wood float finish after consolidation. Afterremoval from the forms, cure the specimens for 28 days in amoist room in accordance with Test Method C192/C192M andSpecification C511.6.10 Upon removal from the moist room, hand wire brushthe specimens on the concrete top surface (wood floated

38、surface). Allow the specimens to dry for two weeks in a 50 %relative humidity (RH) environment before sealing the fourvertical sides with an epoxy sealer, as described in 5.11,inaccordance with the manufacturers recommendation. Place aplastic dam with dimensions, as described in 5.12,onthespecimen,

39、as shown in Fig. 1, and about 13 mm (0.5 in.) fromeach side so that it does not extend over the taped sections ofthe bars (see Fig. 2). Use a silicone caulk to seal the dam fromthe outside, and apply epoxy sealer to the top surface outside ofthe dam.NOTE 7Allowing the specimens to dry before applyin

40、g the concreteepoxy will make the initial exposure to chloride more severe, and moreclosely follow the interlaboratory test program conditions.6.11 Attach wires and resistors.7. Procedure7.1 Support each test specimen on two nonelectricallyconducting supports at least 13-mm (0.5-in.) thick, thus all

41、ow-ing air flow under most of the specimen. Start the test onemonth after the samples are removed from the 100 % RHatmosphere (moist room). Pond the specimens for two weeks at23 6 3C (73 6 5F) with the salt solution, as described in5.10. The volume of this solution is approximately 400 mL ata depth

42、of 40 mm (1.5 in.). Use a plastic loose fitting cover tominimize evaporation. Maintain a relative humidity around thespecimens of 50 6 5 %. After two weeks, vacuum off thesolution and allow the samples to dry for two weeks. Repeatthis cycle.7.2 Measure the voltage across the resistor at the beginnin

43、gof the second week of ponding using the voltmeter defined in4.1. Calculate the current, Ij, from the measured voltage acrossthe 100 resistor, Vj, measured in volts (see Note 8) as:Ij5 Vj/100NOTE 8With the common terminal on the bottom bar, negativevoltages correspond to positive galvanic current (t

44、hat is, the top bar is theanode).7.3 At the same time, measure the corrosion potential of thebars against a reference electrode that is placed in the damcontaining the salt solution (see Practice G3 and Test MethodC876). Connect the voltmeter between the reference electrode(ground or common terminal

45、) and the bars.8. Period of Testing8.1 Monitor the current as a function of time once everyfour weeks, as described in 7.2, until the average integratedmacrocell current of the control specimens is 150 C or greater,as determined in 10.1.8, and at least half the samples showintegrated macrocell curre

46、nts equal to or greater than 150 C(see Note 9).NOTE 9The value of 150 C is consistent with a macrocell current of10 A over six months. The value of 10 A was measured by alllaboratories on all specimens showing corrosion (controls and samplesNOTE 1All measurements in inches (25.4 mm = 1 in.).FIG. 1 C

47、oncrete Beam NOTE 1All measurements in inches (not to scale) (25.4 mm = 1 in.).FIG. 2 Concrete Beam (Side View)G109 07 (2013)3with calcium chloride at 19-mm (34-in.) cover). This degree of integratedmacrocell current is sufficient to ensure the presence of sufficientcorrosion for visual evaluation.8

48、.2 In those cases where the admixtures being tested arecorrosive, end the test three full cycles after an averageintegrated macrocell current of 75 C is observed and theintegrated macrocell current of at least half the specimensbeing tested is equal or greater than 75 C.9. Examination of Embedded Ba

49、rs9.1 At the conclusion of testing, break the specimens andexamine the reinforcement bars for extent of corrosion, mea-sure the corroded area, and record the percentage of corrodedarea recorded, as described in Practice G33.NOTE 10Photograph the bars at the end of the test to provide a recordof the corrosion damage.9.2 Determine the acid soluble chloride content at the depthcorresponding to the cover over the top-reinforcing bar, usingTest Method C1152/C1152M.9.3 Determine the acid soluble chloride content in thespecimen produced for backg