1、Designation: C1202 12C1202 17Standard Test Method forElectrical Indication of Concretes Ability to Resist ChlorideIon Penetration1This standard is issued under the fixed designation C1202; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revi
2、sion, 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. Scope*1.1 This test method covers the determination of the electrical conductance of concrete to provide a ra
3、pid indication of itsresistance to the penetration of chloride ions. This test method is applicable to types of concrete where correlations have beenestablished between this test procedure and long-term chloride ponding procedures such as those described in AASHTO T 259.Examples of such correlations
4、 are discussed in Refs 1-5.21.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes(excluding those in tabl
5、es and figures) shall not be considered as requirements of the standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine t
6、he applicability of regulatorylimitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedb
7、y the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:3C31/C31M Practice for Making and Curing Concrete Test Specimens in the FieldC42/C42M Test Method for Obtaining and Testing Drilled Cores and Sawed Beams of ConcreteC192/C192M Practic
8、e for Making and Curing Concrete Test Specimens in the LaboratoryC670 Practice for Preparing Precision and Bias Statements for Test Methods for Construction Materials2.2 AASHTO Standard:T 259 Method of Test for Resistance of Concrete to Chloride Ion Penetration43. Summary of Test Method3.1 This test
9、 method consists of monitoring the amount of electrical current passed through 50-mm thick slices of 100-mmnominal diameter cores or cylinders during a 6-h period. A potential difference of 60 V dc is maintained across the ends of thespecimen, one of which is immersed in a sodium chloride solution,
10、the other in a sodium hydroxide solution. The total chargepassed, in coulombs, has been found to be related to the resistance of the specimen to chloride ion penetration.4. Significance and Use4.1 This test method covers the laboratory evaluation of the electrical conductance of concrete samples to
11、provide a rapidindication of their resistance to chloride ion penetration. In most cases the electrical conductance results have shown goodcorrelation with chloride ponding tests, such as AASHTO T259, on companion slabs cast from the same concrete mixtures (Refs1-5).1 This test method is under the j
12、urisdiction of ASTM Committee C09 on Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee C09.66 onConcretes Resistance to Fluid Penetration.Current edition approved Feb. 1, 2012June 15, 2017. Published March 2012July 2017. Originally approved in 1991. Last previous edit
13、ion approved in 20102012 as C1202 10.12. DOI: 10.1520/C1202-12.10.1520/C1202-17.2 The boldface numbers in parentheses refer to the list of references at the end of this standard.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. F
14、or Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4 Methods of Sampling and Testing, 1986, American Association of State Highway and Transportation Officials, 444 N. Capitol St., NW, Washington, DC 20001.This document is not an ASTM
15、standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the 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
16、cases only the current versionof the standard as published by ASTM is to be considered the official document.*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 States14.2 This tes
17、t method is suitable for evaluation of materials and material proportions for design purposes and research anddevelopment.4.3 Sample age has significant effects on the test results, depending on the type of concrete and the curing procedure. Mostconcretes, if properly cured, become progressively and
18、 significantly less permeable with time.4.4 This test method was developed originally for evaluations of alternative materials, but in practice its use has evolved toapplications such as quality control and acceptance testing. Factors such as ingredient materials used in concrete mixtures and themet
19、hod and duration of curing test specimens affect the results of this test (See Note 1). When this method is used for mixturequalification and acceptance testing, it is imperative that the curing procedures and the age at time of testing be clearly specified.NOTE 1When using this test for determining
20、 acceptability of concrete mixtures, statistically-based criteria and test age for prequalification, or foracceptance based on jobsite samples, should be stated in project specifications. Acceptance criteria for this test should consider the sources of variabilityaffecting the results and ensure bal
21、anced risk between supplier and purchaser. The anticipated exposure conditions and time before a structure will beput into service should be considered. One approach to establishing criteria is discussed in Ref 6.4.5 Table X1.1 in Appendix X1 provides a qualitative relationship between the results o
22、f this test and the chloride ionpenetrability of concrete.4.6 Care should be taken in interpreting results of this test when it is used on surface-treated concretes, for example, concretestreated with penetrating sealers. The results from this test on some such concretes indicate low resistance to c
23、hloride ionpenetration, while 90-day chloride ponding tests on companion slabs show a higher resistance.4.7 The details of the test method apply to 100-mm nominal diameter specimens. This includes specimens with actual diametersranging from 95 to 100 mm. Other specimen diameters may be tested with a
24、ppropriate changes in the applied voltage cell design(see 7.5 and Fig. 1).4.7.1 For specimen diameters other than 95 mm, the test result value for total charge passed must be adjusted following theprocedure in 11.2. For specimens with diameters less than 95 mm, particular care must be taken in coati
25、ng and mounting thespecimens to ensure that the conductive solutions are able to contact the entire end areas during the test.5. Interferences5.1 This test method can produce misleading results when calcium nitrite has been admixed into a concrete. The results fromthis test on some such concretes in
26、dicate higher coulomb values, that is, lower resistance to chloride ion penetration, than fromtests on identical concrete mixtures (controls) without calcium nitrite. However, long-term chloride ponding tests indicate theconcretes with calcium nitrite were at least as resistant to chloride ion penet
27、ration as the control mixtures.NOTE 2Other admixtures might affect results of this test similarly. Long term ponding tests are recommended if an admixture effect is suspected.5.2 Since the test results are a function of the electrical resistance of the specimen, the presence of reinforcing steel or
28、otherembedded electrically conductive materials may have a significant effect. The test is not valid for specimens containing reinforcingsteel positioned longitudinally, that is, providing a continuous electrical path between the two ends of the specimen.6. Apparatus6.1 Vacuum Saturation Apparatus (
29、see Fig. 2 for example):6.1.1 Separatory Funnel, or other sealable, bottom-draining container with a minimum capacity of 500 mL.6.1.2 Beaker (1000 mL or larger) or other containerCapable of holding concrete specimen(s) and water and of fitting intovacuum desiccator (see 6.1.3).6.1.3 Vacuum Desiccato
30、r250-mm inside diameter or larger. The volume of desiccator shall be large enough to maintainsample immersion throughout the saturation process. Desiccator must allow two hose connections through a rubber stopper andsleeve or through a rubber stopper only. Each connection must be equipped with a sto
31、pcock.6.1.4 Vacuum Pump or AspiratorCapable of maintaining a pressure of less than 50 mm Hg (6650 Pa) in desiccator.NOTE 3Since vacuum will be drawn over water, a vacuum pump should be protected with a water trap, or pump oil should be changed after eachoperation.6.1.5 Vacuum Gage or ManometerAccura
32、te to 65 mm Hg (6665 Pa) over range 0100 mm Hg (013300 Pa) pressure.6.2 Coating Apparatus and Materials:6.2.1 CoatingRapid setting, electrically nonconductive, capable of sealing side surface of concrete cores.6.2.2 Balance or Scale, Paper Cups, Wooden Spatulas, and Disposable BrushesFor mixing and
33、applying coating.6.3 Specimen Sizing Equipment (not required if samples are cast to final specimen size).6.3.1 Movable Bed Water-Cooled Diamond Saw or Silicon Carbide Saw.7. Reagents, Materials, and Test Cell7.1 Specimen-Cell SealantCapable of sealing concrete to poly (methyl methacrylate), for exam
34、ple, Plexiglas, against waterand dilute sodium hydroxide and sodium chloride solutions at temperatures up to 90 C; examples include RTV silicone rubbers,silicone rubber caulkings, other synthetic rubber sealants, silicone greases, and rubber gaskets.C1202 1727.2 Sodium Chloride Solution3.0 % by mass
35、 (reagent grade) in distilled water.7.3 Sodium Hydroxide Solution0.3 N (reagent grade) in distilled water.7.3.1 WarningBefore using NaOH, review: (1) the safety precautions for using NaOH; (2) first aid for burns; and (3) theemergency response to spills, as described in the manufacturers Material Sa
36、fety Data Sheet or other reliable safety literature.NaOH can cause very severe burns and injury to unprotected skin and eyes. Suitable personal protective equipment should alwaysbe used. These should include full-face shields, rubber aprons, and gloves impervious to NaOH. Gloves should be checkedper
37、iodically for pin holes.7.4 Filter PapersNo. 2, 90-mm diameter (not required if rubber gasket is used for sealant (see 7.1) or if sealant can be appliedwithout overflowing from shim onto mesh).7.5 Applied Voltage Cell (see Fig. 1 and Fig. 3)Two symmetric poly (methyl methacrylate) chambers, each con
38、tainingelectrically conductive mesh and external connectors. One design in common use is shown in Fig. 1 and Fig. 3. However, otherdesigns are acceptable, provided that overall dimensions (including dimensions of the fluid reservoir) are the same as shown inFig. 1 and width of the screen and shims a
39、re as shown.FIG. 1 Applied Voltage Cell (Construction Drawing)C1202 1737.6 Temperature Measuring Device (optional)0 to 120C range.7.7 Voltage Application and Data Readout ApparatusCapable of holding 60 6 0.1 V dc across applied voltage cell over entirerange of currents and of displaying voltage accu
40、rate to 60.1 V and current to 61 mA.Apparatus listed in 7.7.1 7.7.5 is a possiblesystem meeting this requirement.7.7.1 VoltmeterDigital (DVM), 3 digit, minimum 099.9 V range, rated accuracy 60.1 %.7.7.2 VoltmeterDigital (DVM), 412 digit, 0200 mV range, rated accuracy 60.1 %.7.7.3 Shunt Resistor100 m
41、V, 10Arating, tolerance 6 0.1 %.Alternatively, a 0.01resistor, tolerance 6 0.1 %, may be used,but care must be taken to establish very low resistance connections.7.7.4 Constant Voltage Power Supply 080 V dc, 02 A, capable of holding voltage constant at 60 6 0.1 V over entire rangeof currents.7.7.5 C
42、ableTwo conductor, AWG No. 14 (1.6 mm), insulated, 600 V.8. Test Specimens8.1 Sample preparation and selection depends on the purpose of the test. For evaluation of materials or their proportions,samples may be (a) cores from test slabs or from large diameter cylinders or (b) 100-mm diameter cast cy
43、linders. For evaluationof structures, samples shall be cores from the structure. Coring shall be done with a drilling rig equipped with a 100-mm diameterdiamond-dressed core bit. Select and core samples following procedures in Test Method C42/C42M. Cylinders cast in thelaboratory shall be prepared f
44、ollowing procedures in Practice C192/C192M.NOTE 4The maximum allowable aggregate size has not been established for this test. Users have indicated that test repeatability is satisfactory onspecimens from the same concrete batch for aggregates up to 25.0 mm nominal maximum size.8.2 When results of th
45、is test method are used for evaluation of materials or mixture proportions based on cast specimens forpurposes of quality control, mixture submittals, or acceptance of concrete, prepare at least two 100-mm diameter cylindricalspecimens in accordance with Practice C192/C192M for concrete mixtures pre
46、pared in the laboratory or Practice C31/C31M fromsamples of fresh concrete obtained in the field. Moist cure specimens in accordance with 8.2.1 for concrete mixtures containingonly portland cement. For concrete mixtures containing supplementary cementitious materials use extended moist curing inFIG.
47、 2 Vacuum Saturation ApparatusFIG. 3 Applied Voltage Cell-Face ViewC1202 174accordance with 8.2.2 (see Note 5) unless the accelerated moist curing method of 8.2.3 is specified (see Note 6). Alternatives tothese curing methods and durations are permitted when specified. Use the same method and durati
48、on of curing for preparingmixture submittals, for subsequent acceptance testing, and for comparing two or more mixtures.8.2.1 Moist CuringCure test specimens for 28 days in accordance with Practice C192/C192M or in accordance with thestandard curing procedure of Practice C31/C31M for specimens prepa
49、red in the field.8.2.2 Extended Moist CuringCure test specimens for 56 days in accordance with Practice C192/C192M for specimensprepared in the laboratory or in accordance with the standard curing procedure of Practice C31/C31M for specimens prepared inthe field.8.2.3 Accelerated Moist CuringProvide 7 days of moist curing in accordance with Practice C192/C192M for specimensprepared in the laboratory or in accordance with the standard curing procedure of Practice C31/C31M for specimens prepared inthe field. After 7 days of moist curing, i
