1、Designation: C 1524 02aStandard Test Method forWater-Extractable Chloride in Aggregate (Soxhlet Method)1This standard is issued under the fixed designation C 1524; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last re
2、vision. 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 provides procedures for sampling andanalysis of aggregate for water-extractable chloride using aSoxhlet ext
3、ractor.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.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its
4、 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 Standards:C 114 Test Methods for Chemical Analysis of HydraulicCement2C 670 Practic
5、e for Preparing Precision and Bias Statementsfor Test Methods for Construction Materials3C 1152/C 1152M Test Method for Acid-Soluble Chloride inMortar and Concrete3C 1218/C 1218M Test Method for Water-Soluble Chloridein Mortar and Concrete3D 75 Practice for Sampling Aggregates4D 1193 Specification f
6、or Reagent Water5E 11 Specification for Wire Cloth and Sieves for TestingPurposes62.2 American Concrete Institute Standard:ACI 222.196 Provisional Standard Test Method for Water-Soluble Chloride Available for Corrosion of EmbeddedSteel in Mortar and Concrete Using the Soxhlet Extractor73. Significan
7、ce 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. This test method isapplicable when aggregates contain a high ba
8、ckground ofnaturally occurring chloride (see ACI 222.196 ). Test MethodC 1152/C 1152M determines acid-soluble chloride and TestMethod C 1218/C 1218M determines water-soluble chloride.Both Test Methods C 1152/C 1152M and C 1218/C 1218Mpulverize the sample to a fine powder or fine granular material.Th
9、e 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 for corrosion.3.2 The Soxhlet extraction apparatus consis
10、ts 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 drips on to the sample.When the water attains a fixed hei
11、ght 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 obtaining aggregatesamples is described in Practice D 75.4.2 S
12、ampling Processing Apparatus, the same as in TestMethod C 1218/C 1218M 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-mm ground-glass fitting to the extractor, and having
13、a 27-mm insidediameter by a 192-mm body length.1This test method is under the jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.69 on Miscellaneous Tests.Current edition approved Dec. 10, 2002. Published January 2003. Originally
14、approved in 2002. Last previous edition approved in 2002 as C 152402.2Annual Book of ASTM Standards, Vol 04.01.3Annual Book of ASTM Standards, Vol 04.02.4Annual Book of ASTM Standards, Vol 04.03.5Annual Book of ASTM Standards, Vol 11.01.6Annual Book of ASTM Standards, Vol 14.02.7Available from Ameri
15、can Concrete Institute (ACI), P.O. Box 9094, FarmingtonHills, MI 48333.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.3.2 Soxhlet Extraction Tube, with a 34/45-mm ground-glass fitting to the condenser and a 24/40-mm ground-glassfi
16、tting to the boiling flask, for holding sample thimbles 25 mmby 80 mm (diameter by height).4.3.3 A 250-mL boiling flask with a 24/40-mm ground-glassfitting.4.3.4 A heating mantel, burner, or hot plate configured forthe flask capable of attaining 200C.4.3.5 Suitable Sample Holder, such as a porous ex
17、tractionthimble 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 chloride in Test MethodsC 114.4.5 pH Paper, short-range 0.0-3.0.4.6 Drying Oven, of sufficient size, capable of continuouslyheating at
18、 110 6 5C.4.7 Sieve, 25.0 mm, complying with Specification E 11.5. Reagents5.1 The reagents required for the chloride determination aregiven in the test method for chloride of Test Methods C 114,and the Procedure section of Test Method C 1218/C 1218M.5.2 Reagent water is either deionized or distille
19、d, conform-ing to the requirements of Specification D 1193 for Type IIIreagent water.6. Sample Preparation6.1 Preparation:6.1.1 For Nominal Maximum Aggregate Sizes 25.0 mm orGreater:Use a jaw crusher or hammer, and reduce the sample so thatthe particles pass a 25.0-mm sieve and are representative of
20、 thesample. Use a sample splitter or use coning and quartering toreduce the sample to between 200 and 500 g. Do not crush thesample to a powder. Oven dry the reduced sample at 110 6 5Cfor2h.FIG. 1 Soxhlet Extraction ApparatusC 1524 02a26.1.2 For Nominal Maximum Aggregate Sizes Less Than25.0 mm :Use
21、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 for 2h.7. Procedure7.1 Mix and cone the reduced sample three times beforesampling each replicate. Obtain a minimum mass of 30.0 g o
22、fthe 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 least 200 mL of reagentwater in the lower flask. Conduct this procedure in triplicate.Make a blank determination by using the Soxhlet
23、 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 the top of thesiphon to properly extract the sample with solution. The sample willinclude aggregate particles and the fines produc
24、ed 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 with the sample. Assemble thecondenser complete with cooling water supply tubing to theextractor and place on the heater. Turn on bo
25、th 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 cycles shall be not less than 70. Onecycle consists of the thimble filling with solution and discharg-ing.NOTE 3Larger-sized Soxhlet ap
26、paratus 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 extraction stage, quantita-tively transfer the solution to a 400-mL beaker by rinsing theboiling flask three times with 10 mL of reagent
27、 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 peroxide, to the extract.Using pH paper, determine the pH of the solution. If the pH ofthe solution is more than 2, add additional 1:
28、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 min. While stirring, heat the coveredbeaker rapidly to boiling. Do not boil for more than a fewseconds. Remove from the hot plate.N
29、OTE 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 methodfor chloride in Test Methods C 114, starting with the procedurethat follows removal of the sample from the hot plate.8. Calcu
30、lation and Reporting8.1 Calculate percent chloride by mass of oven-dry aggre-gate by the reference test method for chloride in Test MethodsC 114.8.2 Report both the individual and average values ofSoxhlet extracted chloride content.8.3 The report shall state whether the sample was fracturedor not fr
31、actured during preparation for testing.9. Precision and Bias9.1 Precision:9.1.1 The single-laboratory standard deviation has beenfound to be 0.0004 %8chloride by mass of aggregate.Therefore, two acceptable test results are not expected to differby more than 0.0015 %.9.1.2 The multilaboratory standar
32、d deviation has beenfound to be 0.0006 %8chloride by mass of aggregate.Therefore, acceptable results obtained in two different labora-tories are not expected to differ by more than 0.0020 %.9.2 BiasThe procedure in this test method has no biasbecause the value of Soxhlet-extracted chloride is define
33、d bythe procedure (see Practice C 670).10. Keywords10.1 aggregate; chloride contentAPPENDIX(Nonmandatory Information)X1. Summary of Soxhlet Round Robin Precision TestingX1.1 Round robin testing to determine within-laboratoryand between-laboratory precision of the Soxhlet method wasperformed by six l
34、aboratories. Each laboratory was providedwith three aggregates to analyze, two containing integralchloride and one aggregate containing chloride absorbed froma marine environment. The aggregates were analyzed asreceived using the Soxhlet method. The results of the inter-laboratory study are found in
35、 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 analyses oflimestone aggregates that contain a large amount of chloridethat is encapsulated or integral within the aggregate shell
36、.These are primarily aggregates from the Niagara Escarpmentextending from southern Ontario down through New York,8These numbers represent, respectively, the (1s) and (d2s) limits as described inPractice C 670.C 1524 02a3northern Michigan and into the Chicago area. Aggregates ofthis type will produce
37、 a high chloride value when ground andanalyzed according to Test Method C 1218/C 1218M and asubstantially lower chloride value analyzed by the Soxhletmethod.X1.3 The Soxhlet method is not intended for marineaggregates or aggregates that contain absorbed chloride asindicated by an insignificant diffe
38、rence between water-soluble(Test Method C 1218/C 1218M) and water-extractable(Soxhlet) chloride.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determin
39、ation of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or wit
40、hdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that yo
41、ur 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 ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (sin
42、gle 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); or through the ASTM website(www.astm.org).TABLE X1.1 Aggregate A Containing Integral ChlorideChloride, % by Mass of SampleLabor
43、atoryData Average Standard Deviationab cXnSn1 0.0012 0.0021 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 us
44、ed to calculate the between-lab average.TABLE X1.2 Aggregate 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 0.001
45、6 0.0020 0.000365 0.0011 0.0010 0.0016 0.0012 0.000326A0.0342 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 0.03502C 1524 02a4
