1、Designation: C586 11Standard Test Method forPotential Alkali Reactivity of Carbonate Rocks as ConcreteAggregates (Rock-Cylinder Method)1This standard is issued under the fixed designation C586; the number immediately following the designation indicates the year oforiginal adoption or, in the case of
2、 revision, 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This test met
3、hod covers the determination of the expan-sion of a specimen of carbonate rock while immersed in asolution of sodium hydroxide (NaOH) at room temperature.The length changes occurring during such immersion indicatethe general level of reactivity of the rock and whether testsshould be made to determin
4、e the effect of aggregate preparedfrom the rock upon the volume change in concrete.1.2 This standard does not 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
5、determine the applica-bility of regulatory limitations prior to use.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.2. Referenced Documents2.1 ASTM Standards:2C294 Descriptive Nomenclature for Constituents of Con-crete Aggre
6、gatesC295 Guide for Petrographic Examination of Aggregatesfor ConcreteC1105 Test Method for Length Change of Concrete Due toAlkali-Carbonate Rock ReactionD75 Practice for Sampling AggregatesD1248 Specification for Polyethylene Plastics ExtrusionMaterials for Wire and CableE177 Practice for Use of th
7、e Terms Precision and Bias inASTM Test Methods3. Terminology3.1 For definitions of terms relating to aggregates used inthis test method, refer to Descriptive Nomenclature C294.4. Summary of Test Method4.1 Small rock cylinders are immersed in a solution ofNaOH except when removed for determination of
8、 lengthchange. The length change of each specimen is periodicallydetermined.5. Significance and Use5.1 This test method is intended to give a relatively rapidindication of the potential expansive reactivity of certaincarbonate rocks that may be used as concrete aggregates. Thetest method has been su
9、ccessfully used in (1) research and (2)preliminary screening of aggregate sources to indicate thepresence of material with a potential for deleterious expansionwhen used in concrete.5.2 The test method is intended as a research and screeningmethod rather than as the basis of a specification requirem
10、ent.It is intended to supplement data from field service records,petrographic examinations according to Guide C295, and testsof aggregate in concrete according to Test Method C1105.5.3 Alkalies participating in the expansive reactions withaggregate constituents in concrete usually are derived from t
11、hehydraulic cement; under certain circumstances they may bederived from other constituents of concrete or from externalsources. Two types of alkali reactivity of aggregates arerecognized: (1) alkali-silica reaction involving certain siliceousrocks, minerals, and artificial glasses, and (2) alkali ca
12、rbonatereaction involving dolomite in certain calcitic dolomites, do-lomitic limestones, and dolostones. This test method is notsuitable as a means to detect alkali-silica reaction.6. Apparatus and Reagents6.1 1 N Sodium Hydroxide SolutionDissolve 40 6 1gofreagent-grade sodium hydroxide (NaOH) in di
13、stilled water,dilute to 1 L and store in a polyethylene bottle.1This test method is under the jurisdiction of ASTM Committee C09 onConcrete and Concrete Aggregates and is the direct responsibility of SubcommitteeC09.26 on Chemical Reactions.Current edition approved Oct. 1, 2011. Published November 2
14、011. Originallyapproved in 1966. Last previous edition approved in 2005 as C58605. DOI:10.1520/C0586-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standard
15、s Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.2 Sawing, Drilling, and Grinding Equipment, suitable forpreparing test spe
16、cimens of the dimensions given in Section 8.This will require one or more rock saws, depending upon thesize of the original sample, a drill press equipped with a smalldiamond core barrel for removing the cylindrical core, and alap, grinder, or suitable modified lathe for shaping the ends ofthe speci
17、mens.6.3 Storage Bottles, approximately 50 to 100-mL capacitywith caps and openings of sufficient size to facilitate removalof specimens. The polyethylene bottle shall be selected toensure that the solution will not be modified by reaction withthe material composing the container, including pigments
18、 orother additives or by transpiration of phases through the wallsof the container. Bottles with wall thickness not less than 0.50mm and composed of high density polyethylene meeting therequirements of Specification D1248 for materials of Type III,Class A, are suitable.6.4 Length Comparator, for con
19、venient and rapid measure-ment of lengths of specimens, the comparator shall be of suchdesign as to provide, permit, or include the following charac-teristics. One type of comparator which has been foundsatisfactory is shown in Fig. 1.6.4.1 A positive means of contact with the conical ends ofthe spe
20、cimen to ensure reproducible measurement of length. AFIG. 1 A Typical Length ComparatorC586 112variety of contact points have been used successfully. Careshould be exercised to ensure that when using specimens withconical ends as described in 8.3, contact is made on the endalong a circle which is co
21、ncentric about the long axis of thespecimen. If the measuring device is a barrel micrometer, itshall have a ratchet stop to produce a constant pressure on thespecimen,6.4.2 A high-grade barrel or dial micrometer graduated toread in 0.001 or 0.002mm units, and accurate within 0.002mm in any 0.020mm r
22、ange, and within 0.004 mm in any0.200mm range. The measuring device should be calibratedthroughout its range to determine both periodic and cumulativeerrors for proper correction of observed data.6.4.3 Asufficient range to allow for small differences amonggage lengths of various specimens. If care i
23、s taken in thefabrication of the specimens, a measuring device with a travelof not less than 7.5 mm provides ample range in the instrument,and6.4.4 A standard or reference shall be used for checking themeasuring device at regular intervals. The bar that serves as areference for the length comparator
24、 shall have an over-alllength of 35 6 2 mm. The length of the bar shall be known toan accuracy of 0.002 mm. The bar shall be fused silica or asteel alloy having a coefficient of thermal expansion not greaterthan 1.0 3 106C. Each end shall be machined to the sameshape as that of the rock specimens. I
25、f a steel alloy is used, itshall be polished (See Note 1). The reference bar shall beplaced in the instrument in the same position each time a lengthmeasurement is made. The micrometer setting of the measur-ing device shall be checked by use of the reference bar at leastat the beginning and end of t
26、he readings made within a half daywhen the apparatus is kept in a room maintained at constanttemperature. It shall be checked more often when kept in aroom where temperature is not constant.NOTE 1Steel alloys with low thermal expansion coefficient should notbe heat treated because they lose their lo
27、w coefficient of thermalexpansion when so treated.7. Sampling7.1 Sample the rock in accordance with the applicablerequirements of Practice D75, except that the sample mass ofeach discernable stratum shall be at least 1 kg, and individualpieces shall be not less than 75 3 75 3 75 mm in size.7.2 Sampl
28、ing should be under the direction of an individualcapable of distinguishing differences in lithology, and thesample of rock should be taken to represent only the particularlithology under consideration bearing in mind the limitationsand significance of this method as stated in Section 5. Eachsample
29、of rock should be in one piece of sufficient size forpreparing the necessary test specimens.7.3 One test specimen will sufficiently represent the sampleof rock unless shale seams or other discontinuities are presentor the bedding is not discernible. In these cases, prepare andtest 3 mutually perpend
30、icular specimens. Of these three speci-mens, testing shall be continued on that one showing thegreatest calculated length change after 28 days of immersion inalkali solution. Discard the remaining two.8. Test Specimens8.1 Test specimens shall be in the form of right circularcylinders or square prism
31、s with conical or plane parallel ends,unless otherwise specified.8.2 The specimen shall have an over-all length of 35 6 5mm and a diameter or sides of 9 6 1 mm for cylinders andprisms respectively. Care shall be exercised in the preparationof the specimens to avoid alteration of the cylindrical surf
32、aceby polishing or with materials which will affect the rate ofentry of alkali solution into the rock.8.3 The included angle of the conical ends shall be approxi-mately 120.8.4 Fabricate specimens having flatend faces in such amanner as to ensure that the faces are parallel to each other andperpendi
33、cular to the major axis of the specimen (see Note 2).NOTE 2End faces parallel to each other and perpendicular to themajor axis of the specimen can be made by turning the specimen in a smalllathe and using tool steel to cut the ends.9. Procedure9.1 Place a position mark on the specimen to permit plac
34、ingthe specimen in the comparator in the same position duringsubsequent measurements.9.2 Measure the length of the test specimen.9.3 Immerse the specimen in distilled water at a roomtemperature in the range of 20 to 27.5 C.9.4 At intervals, remove the specimen, blot to removeexcess surface water and
35、 measure until the change in lengthduring a 24-h water immersion period does not exceed 0.02 %as calculated in 10.1. The length when in this condition is takenas the reference length. The reference length is usuallyachieved after 1 to 4 days of immersion.9.5 Immerse the water-saturated specimens in
36、a bottlecontaining a minimum of 35 mL of 1N NaOH solution perspecimen at room temperature and seal. Immerse no more thantwo specimens in a bottle.9.6 Measure the length of the specimens after 7, 14, 21, and28 days of immersion in NaOH solution and at 4-weekintervals thereafter. If the tests continue
37、 beyond 1 year, makemeasurements at 12-week intervals.9.7 When measurements are made, remove the specimenfrom the bottle, rinse with distilled water, blot to removeexcess surface water and determine its length in the sameposition as during the initial measurement.9.8 After measurement, immediately r
38、eturn the specimen tothe bottle and reseal.9.9 Replace the solution every 6 months during the testingperiod.10. Calculation10.1 Calculate the length change to the nearest 0.01 % ofthe reference length as follows:Dl 5 l1 l0!/l0# 3 100 (1)where:Dl = % length change at test age,l1= length in mm (in.) a
39、t test age, andC586 113l0= reference length after equilibrium in water, as outlinedin 9.4.11. Report11.1 Report the following:11.1.1 Identification number,11.1.2 Type and source of rock,11.1.3 Specimen shape and dimensions if other than rightcircular cylinder,11.1.4 Length change in percent to the n
40、earest 0.01 % ateach time of measurement.Where no times of measurement arespecifically requested, data should be presented for at least thefollowing ages: 1, 4, 8, and 16 weeks and the age at the finalmeasurement.11.1.5 Significant features revealed by examination ofspecimen during and after storage
41、 in alkali solution, such ascracking, warping, splitting, etc., and11.1.6 Other significant information as deemed necessary,such as petrographic and chemical analyses.12. Precision and Bias12.1 Precision:12.1.1 If the results of replicate specimens measured by thesame operator and which presumably r
42、epresent the samematerial, differ by more than 0.10 percentage point for expan-sions less than 1.0 %, it is highly probable that the specimensrepresent rocks that are significantly different in chemicalcomposition, texture, or both.12.1.2 The single-operator, single-comparator, single-specimen preci
43、sion has been found to be 60.02 percentagepoint (3S) as defined in Practice E177.12.1.3 The multi-operator, single-comparator, single-specimen precision has been found to be 60.03 percentagepoint (3S) as defined in Practice E177.12.1.4 The multi-operator, multi-comparator, single-specimen precision
44、has been found to be 60.05 percentagepoint (3S) as defined in Practice E177.12.1.5 In a single laboratory, single operator study of therange of expansion of pairs of rock cylinders from 29 samplesof rock from a single quarry (each pair of cylinders cut from adifferent sample block approximately 75 3
45、 75 3 50 mm insize), the following data were found:12.1.5.1 For pairs of specimens giving average expansion ofless than 0.50 %, the average standard deviation was found tobe 0.0255 %3; therefore, the difference in expansion betweenpairs of cylinders cut from a single block should only exceed0.072 %3
46、one time in twenty when the average expansion isless than 0.50 %.12.1.5.2 For pairs of specimens giving average expansion ofmore than 0.50 %, the average standard deviation was found tobe 0.095 %3; therefore, the difference in expansion betweenpairs of cylinders cut from a single block should only e
47、xceed0.269 %3one time in twenty when the average expansion ismore than 0.50 %.12.2 BiasThe procedure in this test method for measuringexpansion has no bias because the expansion can be definedonly in terms of this test method.13. Keywords13.1 aggregate; alkali reactivity; carbonate rocks; concrete;d
48、eleterious expansionAPPENDIX(Nonmandatory Information)X1. Interpretation of ResultsX1.1 Since the expansion caused by reactions betweencement alkalies and carbonate aggregates is sensitive to subtlechanges in aggregate lithology, the results of measurementsshould be interpreted with full recognition
49、 of the variableswhich would affect the results obtained. The acceptance orrejection of aggregate sources based solely on the results of thistest is not recommended since, in commercial production,expansive and nonexpansive materials may occur in closeproximity and the securing of samples adequately representa-tive of the variability of the production of the source is adifficult task and requires the efforts of an individual trained todistinguish differences in lithology.X1.2 The relationship of the test results to the behavior oflarge quantities of rock from a given
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