1、Designation: C88 13C88/C88M 18Standard Test Method forSoundness of Aggregates by Use of Sodium Sulfate orMagnesium Sulfate1This standard is issued under the fixed designation C88;C88/C88M; the number immediately following the designation indicates the yearof original adoption or, in the case of revi
2、sion, the 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.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope Scope*1.1 This te
3、st method covers the testing of aggregates to estimate their soundness when subjected to weathering action inconcrete or other applications. This is accomplished by repeated immersion in saturated solutions of sodium or magnesium sulfatefollowed by oven drying to partially or completely dehydrate th
4、e salt precipitated in permeable pore spaces. The internal expansiveforce, derived from the rehydration of the salt upon re-immersion, simulates the expansion of water on freezing. This test methodfurnishes information helpful in judging the soundness of aggregates when adequate information is not a
5、vailable from servicerecords of the material exposed to actual weathering conditions.1.2 The values stated in SI or inch pound units shall be regarded separately as standard. The inch pound units are shown inbrackets. The values stated are not exact equivalents; therefore each system shall be used i
6、ndependently of the other. Combiningvalues from the two systems may result in nonconformance.1.3 Some values have only SI units because the inch-pound equivalents are not used in practice.1.4 The values given in parentheses are provided for information purposes only.If the results obtained from anot
7、her standardare not reported in the same system of units as used by this test method, it is permitted to convert those results using the conversionfactors found in the SI Quick Reference Guide.2NOTE 1Sieve size is identified by its standard designation in Specification E11. The alternate designation
8、 given in parentheses is for information onlyand does not represent a different standard sieve size.1.5 This standard does not purport to address all of the safety problems concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appropriate safety
9、 safety, health, and healthenvironmental practices anddetermine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Developm
10、ent of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:3C33C33/C33M Specification for Concrete AggregatesC125 Terminology Relating to Concrete and Concrete AggregatesC136C1
11、36/C136M Test Method for Sieve Analysis of Fine and Coarse AggregatesC670 Practice for Preparing Precision and Bias Statements for Test Methods for Construction MaterialsC702C702/C702M Practice for Reducing Samples of Aggregate to Testing SizeD75D75/D75M Practice for Sampling AggregatesE11 Specifica
12、tion for Woven Wire Test Sieve Cloth and Test SievesE100 Specification for ASTM Hydrometers1 This test method is under the jurisdiction of ASTM Committee C09 on Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee C09.20 onNormal Weight Aggregates.Current edition approve
13、d Aug. 1, 2013Aug. 1, 2018. Published August 2013August 2018. Originally approved in 1931. Last previous edition approved in 20052013 asC88 05.C88 13. DOI: 10.1520/C0088-13.10.1520/C0088_C0088M-18.2 Annex A in Form and Style for ASTM Standards, www.ASTM.org/COMMIT/Blue_Book.dpf3 For referencedASTM s
14、tandards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of a
15、n 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 cases only the current versionof the standard as publi
16、shed 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 States1E323 Specification for Perforated-Plate Sieves for Testing Purpose
17、s3. Terminology3.1 For definitions of general terms used in this test method see Terminology C125.4. Significance and Use4.1 This test method provides a procedure for making a preliminary estimate of the soundness of aggregates for use in concreteand other purposes. The values obtained may be compar
18、ed with specifications, for example Specification C33C33/C33M, that aredesigned to indicate the suitability of aggregate proposed for use. Since the precision of this test method is poor (Section 1213),it may not be suitable for outright rejection of aggregates without confirmation from other tests
19、more closely related to the specificservice intended.4.2 Values for the permitted-loss percentage by this test method are usually different for fine and coarse aggregates, andattention is called to the fact that test results by use of the two salts differ considerably and care must be exercised in f
20、ixing properlimits in any specifications that include requirements for these tests. The test is usually more severe when magnesium sulfate isused; accordingly, limits for percent loss allowed when magnesium sulfate is used are normally higher than limits when sodiumsulfate is used.NOTE 2Refer to the
21、 appropriate sections in Specification C33C33/C33M establishing conditions for acceptance of coarse and fine aggregates whichfail to meet requirements based on this test.5. Apparatus5.1 SievesWith square openings of the following sizes conforming to Specifications E11 or E323, for sieving the sample
22、s inaccordance with Sections 67, 78, and 910:150 m (No. 100) 8.0 mm (516 in.)9.5 mm (38 in.)300 m (No. 50) 12.5 mm (12 in.)16.0 mm (58 in.)600 m (No. 30) 19.0 mm (34 in.)25.0 mm (1 in.)1.18 mm (No. 16) 31.5 mm (114 in.)2.36 mm (No. 8) 37.5 mm (112 in.)50 mm (2 in.)4.00 mm (No. 5) 63 mm (212 in.)larg
23、er sizes by4.75 mm (No. 4) 12.5-mm (12-in.)4.75 mm (No. 4) 12.5 mm (12 in.)spread5.2 ContainersContainers for immersing the samples of aggregate in the solution, in accordance with the procedure describedin this test method, shall be perforated in such a manner as to permit free access of the soluti
24、on to the sample and drainage of thesolution from the sample without loss of aggregate.NOTE 3Baskets made of suitable wire mesh or sieves with suitable openings are satisfactory containers for the samples.5.3 Temperature RegulationSuitable means for regulating the temperature of the samples during i
25、mmersion in the sodiumsulfate or magnesium sulfate solution shall be provided.5.4 Temperature RecorderWith an accuracy of at least 1 F (0.5 C)0.5 C (1 F) and capable of recording the temperatureof the solution at least once every 15 minutesmin for the duration of the test.5.5 BalancesFor fine aggreg
26、ate, a balance or scale accurate within 0.1 g over the range required for this test; for coarseaggregate, a balance or scale accurate within 0.1 % or 1 g, whichever is greater, over the range required for this test.5.6 Drying OvenThe oven shall be capable of being heated continuously at 230 6 9 F (1
27、10 6 5 C)110 6 5 C (230 6 9F) and the rate of evaporation, at this range of temperature, shall be at least 25 g/h for 4 h, during which period the doors of theoven shall be kept closed. This rate shall be determined by the loss of water from 1-L Griffin low-form beakers, each initiallycontaining 500
28、 g of water at a temperature of 70 6 3 F (21 6 2 C),21 6 2 C (70 6 3 F), placed at each corner and the centerof each shelf of the oven. The evaporation requirement is to apply to all test locations when the oven is empty except for thebeakers of water.5.7 Specific Gravity MeasurementHydrometers conf
29、orming to the requirements of Specification E100, or a suitablecombination of graduated glassware and balance, capable of measuring the solution specific gravity within 60.001.6. Special Solutions Required6.1 Prepare the solution for immersion of test samples from either sodium or magnesium sulfate
30、in accordance with 5.1.16.1.1or 5.1.26.1.2 (Note 34). The volume of the solution shall be at least five times the solid volume of all samples immersed at anyone time.C88/C88M 182NOTE 4Some aggregates containing carbonates of calcium or magnesium are attacked chemically by fresh sulfate solution, res
31、ulting in erroneouslyhigh measured losses. If this condition is encountered or is suspected, repeat the test using a filtered solution that has been used previously to test thesame type of carbonate rock, provided that the solution meets the requirements of 5.1.16.1.1 and 5.1.26.1.2 for specific gra
32、vity.6.1.1 Sodium Sulfate SolutionPrepare a saturated solution of sodium sulfate by dissolving a USP or equal grade of the saltin water at a temperature of 77 to 86 F (25 to 30 C).25 to 30 C (77 to 86 F).Add sufficient salt (Note 45), of either the anhydrous(Na2SO4) or the crystalline (Na2 SO410H2O)
33、 form,4 to ensure not only saturation but also the presence of excess crystals whenthe solution is ready for use in the tests. Thoroughly stir the mixture during the addition of the salt and stir the solution at frequentintervals until used. To reduce evaporation and prevent contamination, keep the
34、solution covered at all times when access is notneeded. Allow the solution to cool to 70 6 2 F (21 6 1 C).21 6 1 C (70 6 2 F). Again stir, and allow the solution to remainat the designated temperature for at least 48 h before use. Prior to each use, break up the salt cake, if any, in the container,
35、stirthe solution thoroughly, and determine the specific gravity of the solution. When used, the solution shall have a specific gravitynot less than 1.151 nor more than 1.174. Discard a discolored solution, or filter it and check for specific gravity.NOTE 5For the solution, 215 g of anhydrous salt or
36、 700 g of the decahydrate per litre of water are sufficient for saturation at 71.6 F (22 C).22 C(71.6 F). However, since these salts are not completely stable and since it is desirable that an excess of crystals be present, the use of not less than 350g of the anhydrous salt or 750 g of the decahydr
37、ate salt per litre of water is recommended.6.1.2 Magnesium Sulfate SolutionPrepare a saturated solution of magnesium sulfate by dissolving a USP or equal grade ofthe salt in water at a temperature of 77 to 86 F (25 to 30 C).25 to 30 C (77 to 86 F). Add sufficient salt (Note 56), of eitherthe anhydro
38、us (MgSO4) or the crystalline (MgSO47H2O) (Epsom salt) form, to ensure saturation and the presence of excesscrystals when the solution is ready for use in the tests. Thoroughly stir the mixture during the addition of the salt and stir thesolution at frequent intervals until used. To reduce evaporati
39、on and prevent contamination, keep the solution covered at all timeswhen access is not needed. Allow the solution to cool to 70 6 2 F (21 6 1 C).21 6 1 C (70 6 2 F). Again stir, and allowthe solution to remain at the designated temperature for at least 48 h before use. Prior to each use, break up th
40、e salt cake, if any,in the container, stir the solution thoroughly, and determine the specific gravity of the solution. When used, the solution shall havea specific gravity not less than 1.295 nor more than 1.308. Discard a discolored solution, or filter it and check for specific gravity.NOTE 6For t
41、he solution, 350 g of anhydrous salt or 1230 g of the heptahydrate per litre of water are sufficient for saturation at 73.4 F (23 C).23C (73.4 F). However, since these salts are not completely stable, with the hydrous salt being the more stable of the two, and since it is desirable thatan excess of
42、crystals be present, it is recommended that the heptahydrate salt be used and in an amount of not less than 1400 g/litre of water.6.1.3 Barium Chloride SolutionPrepare 100 mL of 5 % barium chloride solution by dissolving 5 g of BaCl2 in 100 mL ofdistilled water.7. Samples7.1 The sample shall be obta
43、ined in general accordance with Practice D75D75/D75M and reduced to test portion size inaccordance with Practice C702C702/C702M.7.2 Fine AggregateFine aggregate for the test shall be passed through a 9.5-mm (38-in.) sieve. The sample shall be of suchsize that it will yield not less than 100 g of eac
44、h of the following sizes, which shall be available in amounts of 5 % or more,expressed in terms of the following sieves:Passing Sieve Retained on Sieve600 m (No. 30) 300 m (No. 50)1.18 mm (No. 16) 600 m (No. 30)2.36 mm (No. 8) 1.18 mm (No. 16)4.75 mm (No. 4) 2.36 mm (No. 8)9.5 mm (38 in.) 4.75 mm (N
45、o. 4)7.3 Coarse AggregateCoarse aggregate for the test shall consist of material from which the sizes finer than the No. 4 4.75-mm(No. 4) sieve have been removed. The sample shall be of such a size that it will yield the following amounts of the indicated sizesthat are available in amounts of 5 % or
46、 more:Size (Square-Opening Sieves) Mass, g9.5 mm (38 in.) to 4.75 mm (No. 4) 300 519.0 mm (34 in.) to 9.5 mm (38 in.) 1000 10Consisting of:12.5-mm (12-in.) to 9.5-mm (38-in.) material 330 519.0-mm (34-in.) to 12.5-mm (12-in.) material 670 1037.5-mm (1 12-in.) to 19.0-mm (34 in.) 1500 5037.5 mm (1 12
47、 in.) to 19.0 mm (34 in.) 1500 50Consisting of:25.0-mm (1-in.) to 19.0-mm (34-in.) material 500 304 Experience with the test method indicates that a grade of sodium sulfate desig-designatednated by the trade as dried powder, which may be considered as approximately anhydrous, is the most practical f
48、or use. That grade is more economically available than theanhydrous form. The decahydrate sodium sulfate presents difficulties in compounding the required solution on account of its cooling effect on the solution.C88/C88M 18337.5-mm (1 12-in.) to 25.0-mm (1-in.) material 1000 5063-mm (2 12 in.) to 3
49、7.5-mm (1 12 in.) 5000 30063 mm (2 12 in.) to 37.5 mm (1 12 in.) 5000 300Consisting of:50-mm (2 in.) to 37.5-mm (1 12-in.) material 2000 20050-mm (2-in.) to 37.5-mm (1 12-in.) material 2000 20063-mm (2 12-in.) to 50-mm (2-in.) material 3000 300Larger sizes by nominal 12.5-mm (12-in.) spread in sievesize, each fractionConsisting of:75-mm (3-in.) to 63-mm (2 12-in.) material 7000 100090-mm (3 12-in.) to 75-mm (3-in.) material 7000 1000100-mm (4-in.) to
