1、Designation: C1524 02a (Reapproved 2010)Standard Test Method forWater-Extractable Chloride in Aggregate (Soxhlet Method)1This standard is issued under the fixed designation C1524; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、 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 provides procedures for sampling andanalysis of aggregate for water-extractable chloride usi
3、ng aSoxhlet extractor.NOTE 1This test method is to be used when significantly highchloride content has been found in aggregates, concretes, or mortars.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 This standard does no
4、t 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 Standard
5、s:2C114 Test Methods for Chemical Analysis of HydraulicCementC670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsC1152/C1152M Test Method for Acid-Soluble Chloride inMortar and ConcreteC1218/C1218M Test Method for Water-Soluble Chloride inMortar and Co
6、ncreteD75 Practice for Sampling AggregatesD1193 Specification for Reagent WaterE11 Specification for Woven Wire Test Sieve Cloth and TestSieves2.2 American Concrete Institute Standard:ACI 222.196 Provisional Standard Test Method for Water-Soluble Chloride Available for Corrosion of EmbeddedSteel in
7、Mortar and Concrete Using the Soxhlet Extractor33. Significance and Use3.1 Water-extractable chloride, when present in sufficientamount, has a potential to initiate or accelerate corrosion ofmetals, such as steel, embedded in or contacting a cementitioussystem, such as mortar, grout, or concrete. Th
8、is test method isapplicable when aggregates contain a high background ofnaturally occurring chloride (see ACI 222.196 ). Test MethodC1152/C1152M determines acid-soluble chloride and TestMethod C1218/C1218M determines water-soluble chloride.Both Test Methods C1152/C1152M and C1218/C1218M pul-verize t
9、he sample to a fine powder or fine granular material.The Soxhlet method is intended to use nonpulverized material.Results with some aggregates have shown that the Soxhletprocedure extracts an extremely low amount of chloride, withmost of it remaining in the rock, and therefore, it is notavailable fo
10、r corrosion.3.2 The Soxhlet extraction apparatus consists of three sec-tions: the boiling flask, which contains reagent water at thebeginning of the test; the extractor, which contains the sampleinside a thimble; and, the condenser. The extractor functions byboiling the water, which condenses and dr
11、ips on to the sample.When the water attains a fixed height above the sample, theextractor siphons the water from the thimble back to the boilingflask. The process repeats itself until the test is terminated.(Refer to Fig. 1.)4. Apparatus4.1 Sampling Equipment:4.1.1 The apparatus required for obtaini
12、ng aggregatesamples is described in Practice D75.4.2 Sampling Processing Apparatus, the same as in TestMethod C1218/C1218M without pulverization.4.3 Soxhlet Extractor Apparatus, shall have the followingminimum size and consist of the following (see Fig. 1).4.3.1 Reflux-Type Condenser, with a 34/45-m
13、m ground-glass fitting to the extractor, and having a 27-mm insidediameter by a 192-mm body length.4.3.2 Soxhlet Extraction Tube, with a 34/45-mm ground-glass fitting to the condenser and a 24/40-mm ground-glass1This test method is under the jurisdiction of ASTM Committee C09 onConcrete and Concrete
14、 Aggregates and is the direct responsibility of SubcommitteeC09.69 on Miscellaneous Tests.Current edition approved Dec. 1, 2010. Published March 2011. Originallyapproved in 2002. Last previous edition approved in 2002 as C152402a. DOI:10.1520/C1524-02AR11.2For referenced ASTM standards, visit the AS
15、TM 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.3Available from American Concrete Institute (ACI), P.O. Box 9094, FarmingtonHills, MI 48333-9094, http:/w
16、ww.concrete.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.fitting to the boiling flask, for holding sample thimbles 25 mmby 80 mm (diameter by height).4.3.3 A250-mL boiling flask with a 24/40-mm ground-glassfitting.4.3.4 A heat
17、ing mantel, burner, or hot plate configured forthe flask capable of attaining 200C.4.3.5 Suitable Sample Holder, such as a porous extractionthimble having a 25-mm inside diameter and 80-mm externallength.4.4 The apparatus required for the chloride determinationstep is given in the test method for ch
18、loride in Test MethodsC114.4.5 pH Paper, short-range 0.0-3.0.4.6 Drying Oven, of sufficient size, capable of continuouslyheating at 110 6 5C.4.7 Sieve, 25.0 mm, complying with Specification E11.5. Reagents5.1 The reagents required for the chloride determination aregiven in the test method for chlori
19、de of Test Methods C114,and the Procedure section of Test Method C1218/C1218M.5.2 Reagent water is either deionized or distilled, conform-ing to the requirements of Specification D1193 for Type IIIreagent water.6. Sample Preparation6.1 Preparation:6.1.1 For Nominal Maximum Aggregate Sizes 25.0 mm or
20、Greater:Use a jaw crusher or hammer, and reduce the sample so thatthe particles pass a 25.0-mm sieve and are representative of thesample. Use a sample splitter or use coning and quartering toFIG. 1 Soxhlet Extraction ApparatusC1524 02a (2010)2reduce the sample to between 200 and 500 g. Do not crush
21、thesample to a powder. Oven dry the reduced sample at 110 6 5Cfor2h.6.1.2 For Nominal Maximum Aggregate Sizes Less Than25.0 mm :Use a sample splitter or use coning and quartering to reducethe sample to between 200 and 500 g. Do not crush the sampleto a powder. Oven dry the reduced sample at 110 6 5C
22、 for 2h.7. Procedure7.1 Mix and cone the reduced sample three times beforesampling each replicate. Obtain a minimum mass of 30.0 g ofthe sample by sampling from at least four points, record themass to the nearest 0.01 g, and transfer it to the porous sampleholder of the Soxhlet extractor. Place at l
23、east 200 mLof reagentwater in the lower flask. Conduct this procedure in triplicate.Make a blank determination by using the Soxhlet apparatus,with thimble but containing no sample.NOTE 2Replicate sample size can be larger than 30 g; however, thetop of the sample in the thimble needs to be kept below
24、 the top of thesiphon to properly extract the sample with solution. The sample willinclude aggregate particles and the fines produced by crushing.7.1.1 Place the top of the thimble above the top of the glasstube regulating the level at which the water siphons off. Do notcompletely fill the thimble w
25、ith the sample. Assemble thecondenser complete with cooling water supply tubing to theextractor and place on the heater. Turn on both the heater andcondenser cooling water and allow extraction to continue for24 h; the heating rate shall be adjusted to give a cycle every 206 5 min. The number of cycl
26、es shall be not less than 70. Onecycle consists of the thimble filling with solution and discharg-ing.NOTE 3Larger-sized Soxhlet apparatus are available; however, thecycle times will be longer and the total extraction time for 70 cycles willbe about 1.5 to 3 days.7.1.2 At the conclusion of the extra
27、ction stage, quantita-tively transfer the solution to a 400-mL beaker by rinsing theboiling flask three times with 10 mL of reagent water, andtransferring the washings to the beaker. Add 3 6 0.1 mL ofnitric acid that has been diluted one-on-one with water, and add3 6 0.1 mL 30 % solution hydrogen pe
28、roxide, to the extract.Using pH paper, determine the pH of the solution. If the pH ofthe solution is more than 2, add additional 1:1 nitric acid untilthe pH is less than 2. Cover the beaker with a watch glass. Adda stirring bar composed of polytetrafluoroethylene (PTFE) andallow to stand for 1 to 2
29、min. While stirring, heat the coveredbeaker rapidly to boiling. Do not boil for more than a fewseconds. Remove from the hot plate.NOTE 4It is important to keep the beaker covered during heating anddigestion to prevent the loss of volatile chloride.7.1.3 Proceed in accordance with the reference test
30、methodfor chloride in Test Methods C114, starting with the procedurethat follows removal of the sample from the hot plate.8. Calculation and Reporting8.1 Calculate percent chloride by mass of oven-dry aggre-gate by the reference test method for chloride in Test MethodsC114.8.2 Report both the indivi
31、dual and average values ofSoxhlet extracted chloride content.8.3 The report shall state whether the sample was fracturedor not fractured during preparation for testing.9. Precision and Bias9.1 Precision:9.1.1 The single-laboratory standard deviation has beenfound to be 0.0004 %4chloride by mass of a
32、ggregate.Therefore, two acceptable test results are not expected to differby more than 0.0015 %.9.1.2 The multilaboratory standard deviation has beenfound to be 0.0006 %4chloride by mass of aggregate.Therefore, acceptable results obtained in two different labora-tories are not expected to differ by
33、more than 0.0020 %.9.2 BiasThe procedure in this test method has no biasbecause the value of Soxhlet-extracted chloride is defined bythe procedure (see Practice C670).10. Keywords10.1 aggregate; chloride contentAPPENDIX(Nonmandatory Information)X1. Summary of Soxhlet Round Robin Precision TestingX1.
34、1 Round robin testing to determine within-laboratoryand between-laboratory precision of the Soxhlet method wasperformed by six laboratories. Each laboratory was providedwith three aggregates to analyze, two containing integralchloride and one aggregate containing chloride absorbed froma marine envir
35、onment. The aggregates were analyzed asreceived using the Soxhlet method. The results of the inter-laboratory study are found in Tables X1.1-X1.3.NOTE X1.1Data from Aggregate C was not used to calculate within-laboratory and between-laboratory precision.X1.2 The Soxhlet method is intended for the an
36、alyses oflimestone aggregates that contain a large amount of chloridethat is encapsulated or integral within the aggregate shell.These are primarily aggregates from the Niagara Escarpmentextending from southern Ontario down through New York,4These numbers represent, respectively, the (1s) and (d2s)
37、limits as described inPractice C670.C1524 02a (2010)3northern Michigan and into the Chicago area. Aggregates ofthis type will produce a high chloride value when ground andanalyzed according to Test Method C1218/C1218M and asubstantially lower chloride value analyzed by the Soxhletmethod.X1.3 The Sox
38、hlet method is not intended for marineaggregates or aggregates that contain absorbed chloride asindicated by an insignificant difference between water-soluble(Test Method C1218/C1218M) and water-extractable (Soxhlet)chloride.ASTM International takes no position respecting the validity of any patent
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40、any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments
41、 will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by
42、 ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail)
43、; or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).TABLE X1.1 Aggregate A Containing Integral ChlorideChloride, % by Mass of SampleLaboratoryData Average Standard Deviationab cXnSn1 0.0012 0.002
44、1 0.0011 0.0015 0.000552 0.0004 0.0014 0.0009 0.0009 0.000503 0.0021 0.0023 0.0023 0.0022 0.000124 0.0010 0.0008 0.0025 0.0014 0.000935 0.0011 0.0012 0.0011 0.0011 0.000066A0.0226 0.0226 0.0051 0.0168 0.01010AData from Laboratory 6 was not used to calculate the between-lab average.TABLE X1.2 Aggrega
45、te B Containing Integral ChlorideChloride, % by Mass of SampleLaboratoryData Average Standard DeviationabcXnSn1 0.0025 0.0028 0.0022 0.0025 0.000302 0.0021 0.0024 0.0017 0.0021 0.000353 0.0015 0.0018 0.0021 0.0018 0.000304 0.0023 0.0021 0.0016 0.0020 0.000365 0.0011 0.0010 0.0016 0.0012 0.000326A0.0
46、342 0.0301 0.0242 0.0295 0.00503AData from Laboratory 6 was not used to calculate the between-lab average.TABLE X1.3 Aggregate C Containing Absorbed ChlorideChloride, % by Mass of SampleLaboratoryData Average Standard DeviationabcXnSn1 0.2279 0.2780 0.2739 0.2766 0.002342 0.2301 0.2880 0.2954 0.2712 0.035763 0.3201 0.3172 0.3174 0.3182 0.001624 0.3065 0.2824 0.2971 0.2953 0.012155 0.2704 0.2984 0.2511 0.2733 0.023786 0.2088 0.2047 0.2673 0.2269 0.03502C1524 02a (2010)4
