1、Designation: C 1084 02Standard Test Method forPortland-Cement Content of Hardened Hydraulic-CementConcrete1This standard is issued under the fixed designation C 1084; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、 revision. 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 covers the determination of portland-cement content of a sample of hardened hydraulic-cementconcrete.1.2
3、 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are provided forinformation purposes only.1.3 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 t
4、o establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. Disposal of some orall of the chemicals used in this method may require adherenceto EPA or other regulatory guidelines.2. Referenced Documents2.1 ASTM Standards:C 42 Test Met
5、hod for Obtaining and Testing Drilled Coresand Sawed Beams of Concrete2C 114 Test Methods for Chemical Analysis of HydraulicCement3C 670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction Materials3C 702 Practice for Reducing Samples of Aggrgate to Test-ing Size2C
6、823 Practice for Examination and Sampling of HardenedConcrete in Constructions2C 856 Practice for Petrographic Examinations for HardenedConcrete2D 1193 Specification for Reagent Water4E 11 Specification for Wire-Cloth and Sieves for TestingPurposes2E 832 Specification for Laboratory Filter Papers53.
7、 Significance and Use3.1 This test method consists of two independent proce-dures: an oxide-analysis procedure that consists of two sub-procedures and an extraction procedure. Each procedure re-quires a substantial degree of chemical skill and relativelyelaborate chemical instrumentation. Except for
8、 the influence ofknown interferences, determined cement contents are normallyequal to, or slightly greater than, actual values except for theMaleic Acid procedure where results can also be significantlylow when the paste is carbonated (Note 1).NOTE 1With certain limitations, the procedure is also ap
9、plicable forestimating the combined content of portland cement and pozzolan or slagin concretes made with blended hydraulic cement and blends of portlandcement with pozzolans or slags. The results of this test method whenapplied to concretes made with blended cements or pozzolans depend onthe compos
10、ition of the pozzolan, the age of the concrete, the extent ofreaction of the pozzolan and the fact that this test method may determineonly the portland-cement component of a blended cement. The testmethod should be applied to determination of the blended cement contentor the pozzolanic content only
11、by use of calibration concrete samples orother information. Earlier versions of this test method can provide usefulinformation as detailed by Hime6and Minnick.74. Interferences4.1 Many constituents of concrete may interfere with theanalysis of the concrete for portland-cement content. Thefollowing l
12、imited lists of materials have been provided as aguide. The rocks, minerals or mineral admixtures listed willinterfere with the cement content determination to the extent oftheir solubility during the dissolution procedure used. Thesolubility of rocks, minerals or mineral admixtures may dependon the
13、 fineness of the test sample, the water-cement ratio of theconcrete, the extent of hydration, and the age of the concrete(extended exposure to the high pH of the concrete may affectthe solubility of some minerals).4.2 Substances Affecting Calcium Oxide Sub-procedure:1This method is under the jurisdi
14、ction of ASTM Committee C09 on Concreteand Concrete Aggregatesand is the direct responsibility of Subcommittee C09.69 onMiscellaneous Tests.Current edition approved Jan. 10, 2002. Published March 1997. Originallypublished as C 1084 87. Last previous edition C 1084 97.2Annual Book of ASTM Standards,
15、Vol 04.02.3Annual Book of ASTM Standards, Vol 04.01.4Annual Book of ASTM Standards, Vol 11.01.5Annual Book of ASTM Standards, Vol 15.09.6Hime, W. G., “Cement Content,” Significance of Tests and Properties ofConcrete and Concrete-Making Materials, ASTM STP 169B, ASTM, 1978, pp.462470, and “Analyses f
16、or Cement and Other Materials in Hardened Concrete,”Chapter 29, Significant of Tests and Properties of Concrete and Concrete-MakingMaterials, ASTM STP 169C, 1994, pp. 315319.7Minnick, L. J., “Cement-Content, Hardened Concrete,” Significance of Testsand Properties of Concrete and Concrete-Making Mate
17、rials, ASTM STP 169A,ASTM, 1966, p. 326329.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.2.1 The following are soluble in even the cold dilutehydrochloric acid of this procedure and will contribute a highbias to the cement conten
18、t calculated from the soluble calciumoxide: limestone, marble, dolomitic limestone, calcareoussandstone, calcareous chert, and caliche encrusted and calciteor dolomite coated rocks.4.2.2 The following may be soluble depending on the ageand pH of the concrete; whether the mineral present is glassyor
19、crystalline, or weathered or strained; and the fineness of themineral present, and, if soluble, will bias the cement contentcalculated from the soluble calcium oxide high depending onthe calcium content of the minerals: weathered or alteredplagioclase feldspar, caliche-encrusted rocks, altered volca
20、nicrocks (with calcareous inclusions), and many other calciumcontaining rocks.4.2.3 Every percent of soluble calcium oxide that is contrib-uted by soluble aggregate or mineral admixtures will bias thecement content high by approximately 1.6 %.4.2.4 Silica fume may lower the acid solubility of thesam
21、ple and hence bias the result low.4.3 Substances affecting the Soluble Silica Sub-procedure:4.3.1 The following may be soluble depending on the ageand pH of the concrete; whether the aggregate is glassy orcrystalline, or weathered or strained; and the fineness of themineral: chert, opal, chalcedony,
22、 glassy volcanic rock, strainedquartz (highly strained), quartzite, cataclastic rocks (mylonite,phyllonite), gneiss, schist, metagraywacke, and many othersoluble silicon containing rocks or minerals.4.3.2 Every percent of soluble SiO2contributed by aggre-gates or mineral admixtures will bias the rep
23、orted cementcontent high by approximately 4.7 %.4.3.3 Silica fume may lower the acid solubility of thesample and hence bias the result low. If the digestion time ortemperature are sufficient to digest all of the portland cement,the silica fume will also be solubilized and bias the calculatedcement c
24、ontent high.4.4 Substances affecting the Maleic Acid Procedure:4.4.1 The same substances that are soluble in the solublecalcium or the soluble silica subprocedures may be soluble inthe maleic acid procedure. (See 4.2.1, 4.2.2 and 4.3.1.)4.4.2 Every 1 % of the sample that is aggregate or mineraladmix
25、ture dissolved by the maleic acid will bias the cementcontent high by 1 %.4.4.3 Carbonated cement paste may not be soluble in themaleic acid-methanol dissolution and thus may bias the cementcontent results low.4.4.4 The unhydrated iron and aluminum phases of theportland cement may not be soluble in
26、the maleic acid and, ifnot soluble, will bias the cement content low. This may besignificant at early ages and less significant at later ages.5. Apparatus5.1 Choose the apparatus from applicable items given inTest Methods C 114 and from the following:5.1.1 Chipmunk (jaw ore crusher).5.1.2 Disk Pulve
27、rizer.5.1.3 Rotary Mill (rotating puck).5.1.4 Sieve, 300 um (No. 50), 1.18-mm (No. 16) and4.75-mm (No. 4).5.1.5 Ice Bath or electric cooling apparatus.5.1.6 Steam Bath.5.1.7 Funnel, Buchner-type porcelain funnel.5.1.8 Filter Paper, Type II, Class F and Class G as describedin Specification E 832.5.1.
28、9 Beakers, 1000 and 250 mL.5.1.10 Magnetic stirrer, variable speed, with a TFE-fluorocarbon-coated magnetic stirring rod, or an overheadstirrer with a propeller.5.1.11 Volumetric flask, 1000 mL and 500 mL.5.1.12 Filtering flask, 2000 mL.5.1.13 Vacuum pump.5.1.14 Watch glass, 125 mm.6. Reagents and M
29、aterials6.1 Soluble Silica Sub-procedure:6.1.1 Hydrochloric Acid, reagent grade, density 1.19 Mg/m3.6.1.2 Hydrochloric Acid (1:3)Mix 300 mL of hydrochlo-ric acid into 900 mL of water.6.1.3 Hydrochloric Acid (1:9)Mix 100 mL of hydrochlo-ric acid into 900 mL of water.6.1.4 Sodium Hydroxide (10 g/L)Dis
30、solve5gofreagentgrade sodium hydroxide in 200 mL of water and dilute to 500mL.6.1.5 Hydrofluoric Acid, 48 %, reagent grade.6.1.6 Sulfuric Acid, density 1.84 Mg/m3, reagent grade.6.2 Calcium Oxide Sub-procedureUse reagents as re-quired in Test Methods C 114.6.3 Maleic Acid Procedure:6.3.1 Maleic acid
31、, technical grade.6.3.2 Methanol, technical grade, anhydrous.6.3.3 Maleic acid solutionprepare a fresh solution of15 % maleic acid in methanol by dissolving and diluting180 + 1 g of maleic acid with methanol to a final solutionvolume of 1200 millilitres. Prepare this solution fresh daily.Care must b
32、e taken to use methanol only in well ventilatedareas, preferably under a hood, to avoid skin contact andbreathing vapors. Disposal of the maleic acid/methanol solu-tion shall be according to applicable regulations.6.3.4 Fullers eartha clay-like material consisting of aporous colloidal aluminum silic
33、ate. Its high adsorptivity hasbeen found very beneficial for decolorizing and purifyingmaterials.6.4 WaterAll references to water shall be understood tomean reagent water Types I through IV of SpecificationD 1193.7. Sampling7.1 Choose the concrete sample in accordance with thepurposes of the investi
34、gation (Note 2).NOTE 2A standard procedure for sampling hardened concrete is givenin Practice C 823 and a standard procedure for obtaining cores is given inTest Method C 42.7.2 Both the sample for cement content and for density shallhave a minimum length and diameter of four times the nominalmaximum
35、 size of the aggregate (Note 3).NOTE 3A single concrete core taken through the entire depth of theconcrete is ordinarily an appropriate sample. This sample may be sawedC 10842or split lengthwise to provide samples for cement content, density, andpetrographic examination, provided that the length and
36、 thickn ess of thesplit samples for cement content and density meet the minimum sizespecified in 7.2. If the split sample would not meet the minimum sizerequirement, perform the density measurement first, and then crush theentire dry sample for cement content determination. The recommendedmass of co
37、ncrete for cement content determination is 4.5 kg (10 lb). Thismass should be obtained from more than one core when the concrete depthis small and one core will not supply a mass of 4.5 kg (10 lb). If theconcrete sample did not have a mass of 4.5 kg (10 lb) it should be so statedin the final report
38、for the cement content result.7.3 For cement content determination, crush the sample topass a 4.75-mm (No. 4) sieve, mix thoroughly, and obtain arepresentative subsample for analysis by coning and quarteringor by riffle splitting as described in Practice C 702. Thesubsample should have a mass of 0.4
39、5 kg (1 lb).8. Cement Content Procedure8.1 Oxide Analysis Procedure:8.1.1 Crush or grind the subsample prepared as described in7.3 using a chipmunk (jaw ore crusher), a disk pulverizer, or arotary mill (rotating-puck) device, so that all of the materialpasses a 300-m (No. 50) sieve. To minimize prod
40、uction ofvery fine material, use several passes of the sample through theequipment, removing the portion passing the sieve beforeregrinding the remainder of the sample. Thoroughly mix byconing ten times from one paper to another.8.1.2 Dry the crushed or ground material in an oven at 105to 115C (220
41、to 240F) for 3 h and retain the sample in asealed container.8.1.3 Sub-procedure to be used:8.1.3.1 The soluble silica sub-procedure shall be performedin all cases except where a petrographic examination hasindicated there are siliceous aggregates or mineral admixturesthat will be soluble in cold hyd
42、rochloric acid.8.1.3.2 The calcium oxide sub-procedure shall also beemployed unless the aggregate contains a significant amount ofcalcareous components.8.1.3.3 All analyses shall be done in triplicate and theaverage of the three values used in calculating cement content.8.1.4 Soluble Silica Sub-proc
43、edure:8.1.4.1 Introduce 100 mL of dilute hydrochloric acid (1:3)into each of three 250-mL beakers. Cool until within the rangeof 3 to 5C (38 to 41F), using an ice bath or electric coolingapparatus.8.1.4.2 Weigha2gsample to 0.001 g and slowly, over a1-min period, add it to the cold hydrochloric acid.
44、 Maintain the3 to 5C (38 to 41F) temperature for a 5-min period, and stirthe mixture either continuously or at least several times duringthis period (Note 4).NOTE 4Observation of the solution during the introduction of thesample may provide useful information. Considerable effervescenceindicates a s
45、ubstantial amount of calcite or carbonated paste. Delayedeffervescence suggests a dolomitic aggregate. Lack of effervescencesuggests the applicability of the calcium oxide sub-procedure.8.1.4.3 Decant through a Buchner-type porcelain funnelfitted snugly with two disks of a quantitative filter paper
46、forfine precipitates, Type II, Class G filter paper. Once thefiltration has begun, take care so that the mat and accumulatedresidue do not dry completely until the filtration process iscomplete. Regulate the suction so as to maintain a rapid rate ofdripping during the greater part of the filtration.
47、 Retain as muchof the residue in the beaker as possible. Wash twice bydecantation with hot water. Save the filtrate. Transfer the filterpaper from the funnel to the beaker containing the balance ofthe residue, being careful that no residue is lost. Add 75 mL ofhot sodium hydroxide solution (10 g/L)
48、to the residue whilestirring, macerate the filter paper, and digest, covered, on asteam bath for 15 min. During the digestion, occasionally stirthe mixture. Filter all solids, and wash twice with hot wateruntil the filtrate is neutral to litmus. Combine the filtrates.8.1.4.4 The filtrate now contain
49、s the silica in the form ofsilicic acid, either in true solution or in suspension in thehydrochloric acid medium. To ensure analysis of only thesoluble silicon, refilter any filtrate that is cloudy. (Allowing thefiltrate to stand overnight will usually permit suspended silicato settle.) The soluble silica may be analyzed by either of thefollowing procedures 8.1.4.4.1 or 8.1.4.4.2.8.1.4.4.1 Analysis of soluble silica by conversion to silicontetrafluoride with hydrofluoric acidIn the case where theaggregate of the original sample contains substantial amountsof mate
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