1、Designation:C61812C61812a Standard Specication for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete 1 This standard is issued under the xed designation C618; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the
2、 year of last revision.Anumber 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 Department of Defense. 1. Scope* 1.1 This specication covers co
3、al y ash and raw or calcined natural pozzolan for use in concrete where cementitious or pozzolanicaction,orboth,isdesired,orwhereotherpropertiesnormallyattributedtoyashorpozzolansmaybedesired,orwhere both objectives are to be achieved. NOTE 1Finely divided materials may tend to reduce the entrained
4、air content of concrete. Hence, if a y ash or natural pozzolan is added to any concrete for which entrainment of air is specied, provision should be made to ensure that the specied air content is maintained by air content tests and by use of additional air-entraining admixture or use of an air-entra
5、ining admixture in combination with air-entraining hydraulic cement. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 The text of this standard references notes and footnotes, which provide explanatory information.Thes
6、e notes and footnotes (excluding those in tables and gures) shall not be considered as requirements of the standard. 2. Referenced Documents 2.1 ASTM Standards: 2 C125Terminology Relating to Concrete and Concrete Aggregates C311Test Methods for Sampling and Testing Fly Ash or Natural Pozzolans for U
7、se in Portland-Cement Concrete 3. Terminology 3.1 Denitions: 3.1.1 The terms used in this specication are dened in Terminology C125. 3.1.2 y ashthe nely divided residue that results from the combustion of ground or powdered coal and that is transported by ue gasses. NOTE 2This denition of y ash does
8、 not include, among other things, the residue resulting from: (1) the burning of municipal garbage or any other refuse with coal; (2) the injection of lime directly into the boiler for sulfur removal; or (3) the burning of industrial or municipal garbage in incinerators commonly known as incinerator
9、 ash. 4. Classication 4.1 ClassNRaworcalcinednaturalpozzolansthatcomplywiththeapplicablerequirementsfortheclassasgivenherein,such assomediatomaceousearths;opalinechertsandshales;tuffsandvolcanicashesorpumicites,calcinedoruncalcined;andvarious materials requiring calcination to induce satisfactory pr
10、operties, such as some clays and shales. 4.2 Class FFly ash that meets the applicable requirements for this class as given herein. This class of y ash has pozzolanic properties. 4.3 Class CFly ash that meets the applicable requirements for this class as given herein. This class of y ash, in addition
11、 to having pozzolanic properties, also has some cementitious properties. 1 This specication is under the jurisdiction ofASTM Committee C09 on Concrete and ConcreteAggregatesand is the direct responsibility of Subcommittee C09.24 on Supplementary Cementitious Materials. Current edition approved Feb.
12、1, 2012Dec. 15, 2012. Published March 2012January 2013. Originally approved in 1968. Last previous edition approved in 20082012 as C61808a.12. DOI: 10.1520/C061812.10.1520/C061812a. 2 ForreferencedASTMstandards,visittheASTMwebsite,www.astm.org,orcontactASTMCustomerServiceatserviceastm.org.ForAnnualB
13、ookofASTMStandards volume information, refer to the standards Document Summary page on the ASTM website. This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because it may not be techni
14、cally possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version of the standard as published by ASTM is to be considered the official document. *A Summary of Changes section appears at the end of this
15、 standard Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States 1NOTE 3Class F y ash is typically produced from burning anthracite or bituminous coal, but may also be produced from subbituminous coal and from lignite. Class C y ash is typic
16、ally produced from burning lignite or subbituminous coal, and may also be produced from anthracite or bituminous coal. Class C y ashes typically have total calcium contents, expressed as calcium oxide (CaO), that are higher than Class F y ashes. 5. Ordering Information 5.1 The purchaser shall specif
17、y any supplementary optional physical requirements. 5.2 The purchaser shall indicate which procedure, A or B, shall be used when specifying requirements for effectiveness in contribution to sulfate resistance under Table 3. 6. Chemical Composition 6.1 Fly ash and natural pozzolans shall conform to t
18、he requirements as to chemical composition prescribed in Table 1. NOTE 4The chemical component determinations and the limits placed on each do not predict the performance of the y ash or natural pozzolan with hydraulic cement in concrete, but collectively help describe composition and uniformity of
19、the material. 7. Physical Properties 7.1 Fly ash and natural pozzolans shall conform to the physical requirements prescribed in Table 2. Supplementary optional physical requirements are shown in Table 3. 8. Methods of Sampling and Testing 8.1 Sample and test the y ash or natural pozzolan in accordan
20、ce with the requirements of Test Methods C311. 8.2 Use cement of the type proposed for use in the work and, if available, from the mill proposed as the source of the cement, in all tests requiring the use of hydraulic cement. TABLE 1 Chemical Requirements Class N F C Silicon dioxide (SiO 2 ) plus al
21、uminum oxide (Al 2 O 3 ) plus iron oxide (Fe 2 O 3 ), min, % 70.0 70.0 50.0 Sulfur trioxide (SO 3 ), max, % 4.0 5.0 5.0 Moisture content, max, % 3.0 3.0 3.0 Loss on ignition, max, % 10.0 6.0 A 6.0 A The use of Class F pozzolan containing up to 12.0 % loss on ignition may be approved by the user if e
22、ither acceptable performance records or laboratory test results are made available. TABLE 2 Physical Requirements Class N F C Fineness: Amount retained when wet-sieved on 45 m (No. 325) sieve, max, % 34 34 34 Strength activity index: A With portland cement, at 7 days, min, percent of control 75 B 75
23、 B 75 B With portland cement, at 28 days, min, percent of control 75 B 75 B 75 B Water requirement, max, percent of control 115 105 105 Soundness: C Autoclave expansion or contraction, max, % 0.8 0.8 0.8 Uniformity requirements: The density and neness of individual samples shall not vary from the av
24、erage established by the ten preceding tests, or by all preceding tests if the number is less than ten, by more than: Density, max variation from average, % 5 5 5 Percent retained on 45-m (No. 325), max variation, percentage points from average 5 5 5 A The strength activity index with portland cemen
25、t is not to be considered a measure of the compressive strength of concrete containing the y ash or natural pozzolan. The mass of y ash or natural pozzolan specied for the test to determine the strength activity index with portland cement is not considered to be the proportion recommendedfortheconcr
26、etetobeusedinthework.Theoptimumamountofyashornaturalpozzolanforanyspecicprojectisdeterminedbytherequiredproperties oftheconcreteandotherconstituentsoftheconcreteandistobeestablishedbytesting.Strengthactivityindexwithportlandcementisameasureofreactivitywithagiven cement and is subject to variation de
27、pending on the source of both the y ash or natural pozzolan and the cement. B Meeting the 7 day or 28 day strength activity index will indicate specication compliance. C If the y ash or natural pozzolan will constitute more than 20 % by mass of the cementitious material in the project mixture, the t
28、est specimens for autoclave expansion shall contain that anticipated percentage. Excessive autoclave expansion is highly signicant in cases where water to cementitious material ratios are low, for example, in block or shotcrete mixtures. C61812a 29. Storage and Inspection 9.1 The y ash or natural po
29、zzolan shall be stored in such a manner as to permit easy access for proper inspection and identication of each shipment. 9.2 Inspection of the material shall be made as agreed upon by the purchaser and the seller as part of the purchase contract. 10. Rejection 10.1 Thepurchaserhastherighttorejectma
30、terialthatfailstoconformtotherequirementsofthisspecication.Rejectionshall be reported to the producer or supplier promptly and in writing. 10.2 The purchaser has the right to reject packages varying more than 5% from the stated weight. The purchaser also has the righttorejecttheentireshipmentiftheav
31、erageweightofthepackagesinanyshipment,asshownbyweighing50packagestaken at random, is less than that specied. 10.3 The purchaser has the right to require that material in storage prior to shipment for a period longer than 6 months after testing be retested. The purchaser has the right to reject such
32、material if it fails to meet the neness requirements. TABLE 3 Supplementary Optional Physical Requirements NOTE 1These optional requirements apply only when specically requested. Class N F C Increase of drying shrinkage of mortar bars at 28 days, max, difference, in %, over control A 0.03 0.03 0.03
33、Uniformity Requirements: In addition, when air-entraining concrete is specied, the quantity of air- entraining agent required to produce an air content of 18.0 vol % of mortar shall not vary from the average established by the ten preceding tests or by all preceding tests if less than ten, by more t
34、han, % 20 20 20 Effectiveness in Controlling Alkali-Silica Reaction: B Expansion of test mixture as percentage of low-alkali cement control, at 14 days, max, % 100 100 100 Effectiveness in Contributing to Sulfate Resistance: C Procedure A: Expansion of test mixture: For moderate sulfate exposure aft
35、er 6 months exposure, max, % 0.10 0.10 0.10 For high sulfate exposure after 6 months exposure, max, % 0.05 0.05 0.05 Procedure B: Expansion of test mixture as a percentage of sulfate resistance cement control after at least 6 months exposure, max,% 100 100 100 A Determination of compliance or noncom
36、pliance with the requirement relating to increase in drying shrinkage will be made only at the request of the purchaser. B Fly ash or natural pozzolans meeting this requirement are considered as effective in controlling alkali silica reactions as the use of the low-alkali control cement used in the
37、evaluation. However, the y ash or natural pozzolan shall be considered effective only when used at percentages by mass of the total cementitious material equal to or exceeding that used in the tests and when the alkali content of the cement to be used does not exceed that used in the tests by more t
38、han 0.05 %. SeeAppendix XI, Test Methods C311. C Fly ash or natural pozzolan shall be considered effective only when the y ash or natural pozzolan is used at percentages, by mass, of the total cementitious material within 2 % of those that are successful in the test mixtures or between two percentag
39、es that are successful, and when the C 3 Acontent of the project cement is less than, or equal to, that which was used in the test mixtures. See Appendix X2 of Test Method C311. C61812a 311. Packaging and Package Marking 11.1 When the y ash or natural pozzolan is delivered in packages, the class, na
40、me, and brand of the producer, and the weight of the material contained therein, shall be plainly marked on each package. Similar information shall be provided in the shipping invoices accompanying the shipment of packaged or bulk material. 12. Suppliers Certication 12.1 Upon request of the purchase
41、r, in the contract or the order, a suppliers report shall be furnished stating the results of tests made on samples of the material and certifying the product conforms to all applicable requirements of this specication. In addition, the report shall include the percentages of magnesium oxide (MgO),
42、sodium oxide (Na 2 O), potassium oxide (K 2 O), and calcium oxide (CaO), all determined as described in Test Methods C311. The report shall also include the total alkali content of the material, expressed as equivalent percentage of sodium oxide (Na 2 Oe). NOTE 5Guidance on preparing the suppliers r
43、eport is provided in Appendix X1. 13. Keywords 13.1 y ash; natural pozzolan; pozzolans APPENDIX (Nonmandatory Information) X1. SUPPLIERS CERTIFICATION REPORT X1.1 To provide uniformity for reporting the results of tests performed on pozzolans under this specication, and affirming compliance to the a
44、pplicable limits of this standard, an example report of analysis is shown in Fig. X1.1. SUMMARY OF CHANGES Committee C09 has identied the location of selected changes to this specication since the last issue, C61812, that may impact the use of this specication. (Approved December 15, 2012) (1) Added
45、 new Section 12 Suppliers Certication. (2) Added new Note 5 to refer to example of suppliers report. (3) Added example of a suppliers report in new Appendix X1. C61812a 4SUMMARY OF CHANGES Committee C09 has identied the location of selected changes to this specication since the last issue, C61808a,
46、that may impact the use of this specication. (Approved February 1, 2012) (1) Revised Note 3 to remove reference to 10 % CaO. FIG. X1.1Example of a Suppliers Report C61812a 5ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentione
47、d in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility. Thisstandardissubjecttorevisionatanytimebytheresponsibletechnicalcommitteeandmustbereview
48、edeveryveyearsand ifnotrevised,eitherreapprovedorwithdrawn.Yourcommentsareinvitedeitherforrevisionofthisstandardorforadditionalstandards and should be addressed toASTM International Headquarters.Your comments will receive careful consideration at a meeting of the responsible technical committee, whi
49、ch you may attend. If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards, at the address shown below. This standard is copyrighted byASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA19428-2959, United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the above address or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.or
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