1、Designation: C1152/C1152M 04 (Reapproved 2012)1Standard Test Method forAcid-Soluble Chloride in Mortar and Concrete1This standard is issued under the fixed designation C1152/C1152M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, t
2、he year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTEEditorial changes were made throughout in December 2012.1. Scope1.1 This test method2provides procedures for the s
3、amplingand analysis of hydraulic-cement mortar or concrete forchloride that is acid soluble under the conditions of test. Inmost cases, acid-soluble chloride is equivalent to total chloride.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. Some va
4、lues haveonly SI units because the inch-pound equivalents are not usedin practice.NOTE 1Sieve size is identified by its standard designation in Speci-fication E11. The alternative designation in parentheses is for informationonly and does not represent a different standard sieve size.1.3 The text of
5、 this standard references notes and footnotesthat provide explanatory information. These notes and foot-notes shall not be considered as 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
6、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:3C42/C42M Test Method for Obtaining and Testing DrilledCores and Sawed Beams of ConcreteC114 Test Methods
7、for Chemical Analysis of HydraulicCementC670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsC702/C702M Practice for Reducing Samples of Aggregateto Testing SizeC823/C823M Practice for Examination and Sampling ofHardened Concrete in ConstructionsC1084 T
8、est Method for Portland-Cement Content of Hard-ened Hydraulic-Cement ConcreteD1193 Specification for Reagent WaterE11 Specification for Woven Wire Test Sieve Cloth and TestSieves3. Significance and Use3.1 The amount of acid-soluble chloride in most hydraulic-cement systems is equal to the total amou
9、nt of chloride in thesystem. However, some organic substances that may be intro-duced into mortar or concrete contain chloride that is initiallyacid-insoluble that can eventually ionize and thus becomeacid-soluble or water-soluble after a period of exposure in thevery alkaline cement system.3.2 Sulf
10、ides are known to interfere with the determination ofchloride content. Blast-furnace slag aggregates and cementscontain sulfide sulfur in concentrations that can cause suchinterference and produce erroneously high test results. Treat-ment with hydrogen peroxide, as discussed in Test MethodsC114, is
11、used to eliminate such interference.3.3 There are aggregates that contain chloride that is notavailable for corrosion. Such chloride will be detected by theuse of this method.44. Apparatus4.1 Sampling Equipment4.1.1 The apparatus required for obtaining samples bycoring or sawing is described in Test
12、 Method C42/C42M.4.1.2 Use the following apparatus for sampling by drilling(pulverization):4.1.2.1 Rotary Impact Drill and drill or pulverizing bits ofsufficient diameter to provide a representative sample ofsufficient size for testing.1This test method is under the jurisdiction of ASTM Committee C0
13、9 onConcrete and Concrete Aggregatesand is the direct responsibility of SubcommitteeC09.69 on Miscellaneous Tests.Current edition approved Dec. 15, 2012. Published January 2013. Originallyapproved in 1990. Last previous edition approved in 2004 as C1152 041. DOI:10.1520/C1152_C1152M-04R12E01.2This t
14、est method is based on a report by Clear, K. C., and Harrigan, E. T.,“Sampling and Testing for Chloride Ion in Concrete,” Report No. FHWA-RD77-85,Federal Highway Administration, Washington, DC, Aug. 1977 (Available as PB275-428/AS National Technical Information Services).3For referenced ASTM standar
15、ds, 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.4For more information, see “The Determination of the Chloride Content ofConcrete,” by Bri
16、an B. Hope, John A. Page and John S. Poland, Cement andConcrete Research, Volume 15, Number 5, Pergamon Press, New York, September1985, pp. 863-870.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.1.2.2 Spoon or other suitable means
17、to remove pulverizedsample material from drill hole without contamination.4.1.2.3 Sample Containers capable of maintaining samplesin an uncontaminated state.4.2 Sample Processing ApparatusThe apparatus requiredfor processing samples shall be chosen for its suitability for thepurposes of the investig
18、ation, and frequently includes a con-crete saw and one or more pulverizers.4.2.1 Samples more than 25 mm (1 in.) in maximumdimension shall be reduced in size by use of a jaw crusher orbroken into smaller pieces by hammering carefully to avoidloss of smaller pieces.4.2.2 Crush particles less than 25
19、mm (1 in.) in maximumdimension using a rotating puck grinding apparatus, or byusing a disk pulverizer, or mortar and pestle operated to restrictto negligible levels the loss of fine particles.4.2.3 Sieve, 850-m (No. 20), which shall comply withSpecification E11.4.3 Chloride Determination4.3.1 Balanc
20、e, shall be capable of reproducing resultswithin 0.0002 g with an accuracy of 6 0.0002 g. Direct-reading balances shall have a sensitivity not exceeding 0.0001g. Conventional two-pan balances shall have a maximumsensibility reciprocal of 0.0003 g. Any rapid weighing devicethat may be provided, such
21、as a chain, damped motion, orheavy riders, shall not increase the basic inaccuracy by morethan 0.0001 g at any reading and with any load within the ratedcapacity of the balance.4.3.2 Stirrer, magnetic variable speed, with a TFE-fluorocarbon coated magnetic stirring bar.4.3.3 Chloride, Silver/Sulfide
22、 Ion Selective Electrode,orasilver billet electrode coated with silver chloride (see Note 2)with an appropriate reference electrode.4.3.4 Potentiometer, with millivolt scale readable to 1 mVor better. A digital readout is preferred but not required.NOTE 2See Note 67 of Test Methods C114 for a discus
23、sion of suitableelectrodes and coating methods.4.4 Glazed PaperPaper to which fine particles do notadhere, for use as described in 7.1.5. Reagents5.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the
24、specifications of the Commit-tee onAnalytical Reagents of theAmerican Chemical Society5.Other grades may be used, provided it is first ascertained thatthe reagent is of sufficiently high purity to permit its usewithout lessening the accuracy of the determination.5.1.1 Sodium Chloride (NaCl).5.1.2 Si
25、lver Nitrate (AgNO3).5.1.3 Potassium Chloride (KCl), (required for silver billetelectrode only).5.1.4 Reagent Water conforming to the requirements ofSpecification D1193 for Type III reagent water.5.1.5 Sodium Chloride, Standard Solution (0.05 N NaCl)Dry sodium chloride at 105 to 110 C to a constant
26、mass.Weigh 2.9222 g of dried reagent. Dissolve in water and diluteto exactly 1 L in a volumetric flask and mix thoroughly. Thissolution is the standard and requires no further standardization.5.1.6 Silver Nitrate, Standard Solution (0.05 N (AgNO3)Dissolve 8.4938 g of silver nitrate in water. Dilute
27、to 1 L in avolumetric flask and mix thoroughly. Standardize against 5.00mL of standard 0.05 N sodium chloride solution diluted to 150mL with water following the titration test method given in 8.1beginning with the second sentence. The exact normality shallbe calculated from the average of three dete
28、rminations asfollows:N = 0.25/V, where:N = normality of AgNO3solution,0.25 = milliequivalents NaCl (5.0 0.05 N), andV = volume of AgNO3solution, mL.Commercially available standard solutions may be usedprovided the normality is checked according to the standard-ization procedure.5.1.7 Methyl Orange I
29、ndicatorPrepare a solution contain-ing2gofmethyl orange per litre of 95 % ethyl alcohol.5.1.8 Nitric Acid (1+1).5.1.9 Hydrogen Peroxide (30 %).6. Sampling6.1 Select the sample in accordance with Practice C823/C823M or as required for the purpose of the investigation.6.1.1 Because of the small nomina
30、l maximum size of theaggregate in a mortar, pieces of mortar having a mass of 10 gor more will be representative of a rather large volume ofmortar.6.1.2 Take concrete cores in accordance with Test MethodC42/C42M unless otherwise specified.NOTE 3Concrete cores taken in accordance with Test MethodC42/
31、C42M may be cut longitudinally to provide a 12-mm 12-in. thicksection generally representative of the core, or cut laterally into 12-mm12-in. thick disks representative of the concrete core at various depths.Concrete farthest from a surface into which chloride has penetrated oftenprovides chloride d
32、ata close to that of the originally placed fresh concrete.The cooling water from core cutting may dissolve some of the chloride.6.1.3 Powdered concrete obtained by use of a rotary impactdrill is frequently used in determining chloride concentrationwith depth in bridge decks, pavements, etc. Such sam
33、ples maybe unrepresentative, especially when the nominal maximumcoarse aggregate size is 25 mm (1 in.) or more. Thus, severalsuch samples should be combined, or the data used with care.Procedures for this method of sampling are as follows:6.1.3.1 Using the rotary impact drill, drill perpendicular to
34、the concrete surface or parallel to the axis of a cored specimento a specified depth or a depth sufficient to obtain a represen-tative sample of the concrete mixture of at least 20 g ofpowdered material. To prevent sample contamination, avoidcontact of sample with hands and other sources of perspira
35、tion.5Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharm
36、acopeiaand National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,MD.C1152/C1152M 04 (2012)12Clean all sampling tools prior to each sampling operation (SeeNote 4). No lubricants shall be used during drilling.NOTE 4Sampling tools may be cleaned with a brush, cloth, ethylalcohol ri
37、nse, water rinse, or other method that will not contaminate thesample.6.1.3.2 Transfer powdered sample into sample containerusing a spoon or other suitable means.7. Sample Preparation7.1 Pulverize the sample so that all the material will pass a850-m (No. 20) sieve. Thoroughly blend the material byco
38、ning as described in Practice C702/C702M from one glazedpaper to another at least 10 times.8. Procedure8.1 Determine the mass of approximately 10 g of sample tothe nearest 0.01 g and transfer to a 250 mLbeaker. Disperse thesample with 75 mL of water. Slowly add 25 mL of dilute (1+1)nitric acid and s
39、tir with a glass rod, breaking up any lumps ofsample. If the smell of hydrogen sulfide is strongly present, add3 mL of hydrogen peroxide (See Note 5). Add 3 drops ofmethyl orange indicator to the beaker and stir. Cover the beakerwith a watch glass and allow to stand for 1 to 2 minutes. If thesolutio
40、n above the settled solids is not pink colored, add morenitric acid dropwise while stirring until a pink or reddish colorpersists, then add 10 additional drops of nitric acid and stir.Heat the covered beaker rapidly to boiling and remove fromhot plate. Do not allow sample to boil more than a few sec
41、onds(See Note 6). Make a blank determination using 75 mL ofwater in place of sample.NOTE 5Slags and slag cements contain sulfide sulfur in concentra-tions that can interfere with chloride determination unless oxidized withhydrogen peroxide.NOTE 6To prevent loss of chloride by volatilization, it is i
42、mportant tokeep the beaker covered during heating and digestion. Ten seconds ofboiling is sufficient. Excessive amounts of acid can erode the silverchloride coating on the silver billet electrode prematurely. A slurry that isonly slightly acidic is sufficient.8.2 Filter the sample through a 9-cm coa
43、rse-textured filterpaper in a 250 mL or 500 mL Buchner funnel and filtrationflask using suction. Rinse the beaker and the filter paper twicewith small portions of water. Transfer the filtrate from the flaskto a 250 mL beaker and rinse the flask once with water. Theoriginal beaker may be used (See No
44、te 7). Cool the filtrate toroom temperature. The volume should not exceed 175 mL.NOTE 7It is not necessary to clean all the slurry residue from the sidesof the beaker, nor is it necessary that the filter remove all the fine material.The titration may take place in a solution that contains a small am
45、ount ofsolid matter.8.3 For instruments equipped with a dial readout it isnecessary to establish an approximate “equivalence point“ byimmersing the electrodes in a beaker of water and adjusting theinstrument to read about 20 mV lower than mid-scale. Recordthe approximate millivoltmeter reading. Remo
46、ve the beakerand wipe the electrodes with absorbent paper.8.4 Pipet 2.00 mL of standard 0.05 N NaCl solution into thecooled sample beaker (See Note 8). Place the beaker on amagnetic stirrer and add a TFE-fluorocarbon coated stir bar.Immerse the electrodes into the solution, taking care that thestir
47、bar does not strike the electrodes. Begin stirring gently.Place the delivery tip of the 10 mL buret filled to the zero markwith standardized 0.05 N AgNO3in (preferably) or above thesample solution (See Note 9).NOTE 8It is advisable to maintain constant temperature duringmeasurement, as the solubilit
48、y of silver chloride varies markedly withtemperature at low concentrations.NOTE 9If the tip of the buret is out of the solution, any adheringdroplet should be rinsed into the beaker with a few millilitres of waterfollowing each titration increment.8.5 Gradually titrate, record the amount of standard
49、 0.05 Nsilver nitrate solution required to bring the millivoltmeterreading to -60.0 mV of the equivalence point determined in thewater.8.6 Continue the titration with 0.20 mL increments. Recordthe buret reading and the corresponding millivoltmeter reading.Allow sufficient time between each addition for the electrodesto reach equilibrium with the sample solution (See Note 10).NOTE 10Experience has shown that acceptable readings are obtainedwhen the minimum scale reading does not change within a 5-s period.8.7 As the equivalence point is approached, th
