ASTM C827 C827M-2016 Standard Test Method for Change in Height at Early Ages of Cylindrical Specimens of Cementitious Mixtures《碳化混合物圆柱形试样的早期高度变化的标准试验方法》.pdf

《ASTM C827 C827M-2016 Standard Test Method for Change in Height at Early Ages of Cylindrical Specimens of Cementitious Mixtures《碳化混合物圆柱形试样的早期高度变化的标准试验方法》.pdf》由会员分享，可在线阅读，更多相关《ASTM C827 C827M-2016 Standard Test Method for Change in Height at Early Ages of Cylindrical Specimens of Cementitious Mixtures《碳化混合物圆柱形试样的早期高度变化的标准试验方法》.pdf（5页珍藏版）》请在麦多课文档分享上搜索。

1、Designation: C827/C827M 10C827/C827M 16Standard Test Method forChange in Height at Early Ages of Cylindrical Specimens ofCementitious Mixtures1This standard is issued under the fixed designation C827/C827M; the number immediately following the designation indicates the yearof original adoption or, i

2、n the case of revision, 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.1. Scope*1.1 This test method covers the determination of change in height of cylindrical spec

3、imens from the time of molding until themixture is hard.1.2 This test method covers height change measurements at early ages for cementitious mixtures of paste, grout, mortar, andconcrete.1.3 This test method is intended for determination of changes in height that occur from the time of placement un

4、til the specimenis fully hard. These include shrinkage or expansion due to hydration, settlement, evaporation, and other physical and chemicaleffects.1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in eachsystem may not be exa

5、ct equivalents; therefore, each system shall be used independently of the other. Combining values from thetwo systems may result in non-conformance with the standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof

6、the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.1.6 The text of this test method references notes and footnotes that provide explanatory information. These notes and footnotesshall not be considered

7、as requirements of the test method.2. Referenced Documents2.1 ASTM Standards:2C109/C109M Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2-in. or 50-mm Cube Specimens)C125 Terminology Relating to Concrete and Concrete AggregatesC138/C138M Test Method for Density (Unit Weight)

8、, Yield, and Air Content (Gravimetric) of ConcreteC143/C143M Test Method for Slump of Hydraulic-Cement ConcreteC185 Test Method for Air Content of Hydraulic Cement MortarC191 Test Methods for Time of Setting of Hydraulic Cement by Vicat NeedleC192/C192M Practice for Making and Curing Concrete Test S

9、pecimens in the LaboratoryC305 Practice for Mechanical Mixing of Hydraulic Cement Pastes and Mortars of Plastic ConsistencyC403/C403M Test Method for Time of Setting of Concrete Mixtures by Penetration ResistanceC670 Practice for Preparing Precision and Bias Statements for Test Methods for Construct

10、ion MaterialsC807 Test Method for Time of Setting of Hydraulic Cement Mortar by Modified Vicat NeedleC939 Test Method for Flow of Grout for Preplaced-Aggregate Concrete (Flow Cone Method)C953 Test Method for Time of Setting of Grouts for Preplaced-Aggregate Concrete in the LaboratoryC1437 Test Metho

11、d for Flow of Hydraulic Cement Mortar1 This test method is under the jurisdiction of ASTM Committee C09 on Concrete and Concrete Aggregates and is the direct responsibility of Subcommittee C09.68 onVolume Change.Current edition approved June 15, 2010April 1, 2016. Published July 2010June 2016. Origi

12、nally approved in 1975. Last previous edition approved in 20052010 asC827C827 10. 01a (2005). DOI: 10.1520/C0827_C0827M-10.DOI: 10.1520/C0827_C0827M-16.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Sta

13、ndardsvolume 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 an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possibl

14、e 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 published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyri

15、ght ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13. Terminology3.1 DefinitionsThe terms used in this test method are defined in Terminology C125.3.2 Definitions of Terms Specific to This Standard:3.2.1 early-age change in height, nthe measur

16、ed increase or decrease in height of a laterally confined cylindrical test specimenfrom the time of molding to when the mixture becomes hard. The user may want to define this age as the time when a companionspecimen of the same batch has reached the time of final setting by Test Method C191 (paste),

17、 C953 (mortar or grout),C403/C403M (concrete), or establish a predetermined age in minutes from the time the specimen is cast as the defined age to recordthe final measurement. Changes in height are measured and expressed as a positive or negative change in the height of a testspecimen that is restr

18、ained from lateral movement.4. Significance and Use4.1 This test method provides a means for comparing the relative shrinkage or expansion of cementitious mixtures. It isparticularly applicable to grouting, patching, and form-filling operations where the objective is to completely fill a cavity or o

19、therdefined space with a freshly mixed cementitious mixture that will continue to fill the same space at time of hardening. It wouldbe appropriate to use this test method as a basis for prescribing mixtures having restricted or specified volume change before themixture becomes hard.4.2 This test met

20、hod can be used for research purposes to provide information on volume changes taking place in cementitiousmixtures between the time just after mixing and the time of hardening. However, the specimen used in this test method is notcompletely unrestrained so that the measurements are primarily useful

21、 for comparative purposes rather than as absolute values.Further, the degree of restraint to which the specimen is subjected varies with the viscosity and degree of hardening of the mixture.5. Apparatus (see Fig. 1)5.1 Projected Light Source, a lamp and a condensing lens of sufficient intensity to a

22、dequately project a light beam on a wallabout 5 m 15 ft from the light source. Protect the test specimen from heat from the light source and limit air movement (Note1).NOTE 1Placing a sheet of transparent glass or plastic between the light source and the test specimens may be beneficial.5.2 Indicato

23、r Ball, a spherical ball of nonabsorptive material with a density that is 55 6 5 % of the density of the cementitiousmixture being tested, having a diameter not more than 16 mm 58 in. nor less than 6 mm 14 in., and composed of materials thathave no reaction with the cementitious mixture during the t

24、est period.3NOTE 2Adensity of approximately 1.2 Mg/m3 has been found appropriate for most uses of this test method. The density of the cementitious mixturemay be calculated from values for “unit weight” obtained using Test Method C138/C138M (concrete) or C185 (mortar, grout, or paste).5.3 Magnifying

25、 Lens System, a magnifying lens system such that the image of the indicator ball produced by the projected lightsource is cast on the indicating chart about 5 m 15 ft away at a magnification of 90110, mounted so as not to touch the testspecimen when a test is in progress (see Note 3), and having a s

26、eparate magnifying lens system for each specimen testedsimultaneously.NOTE 3One magnifying lens system that has been found acceptable consists of two lenses: a projection and a relay lens enclosed in a sealed tube.In this system, the relay lens is located nearer the test specimen and has a focal len

27、gth of 50.8 mm 2 in. and is located approximately 115 mm 412in. from the indicator ball. The projection lens has a focal length of 41.4 mm 158 in., and relative aperture of f1.6 and is 133.1 mm 514 in. from therelay lens.3 An 11-mm 716-in. nylon plastic indicator ball has been found acceptable for m

28、ost tests and is available from U.S. Plastics Corp., 1390 Neubrecht Rd., Lima, OH 45801.FIG. 1 Apparatus for Early Change in HeightC827/C827M 1625.4 Indicating Charts, composed of stiff material approximately 600 mm 24 in. high by 250 mm 10 in. wide, with a whitesurface and a vertical black line 2 m

29、m 116 in. wide, centered and running the complete length of the chart, and a horizontal blackline 1 mm 132 in. in width midway on the chart, identified as the zero (0) or starting line, and 2-mm 0.1-in. horizontalgraduations above and below the zero line on the entire length of the vertical line, an

30、d a means for attaching this chart verticallyand firmly to a distant wall.5.5 Molds, rigid, watertight molds with a smooth interior surface made of steel, cast iron, or other nonabsorbent materialnonreactive with the cementitious mixture being tested, cylindrical in shape, with internal height twice

31、 the internal diameter. Threesizes of molds are used in this test method with heights of 100, 150, 300 mm 4, 6, 12 in.5.6 Rods, two straight, steel tamping rods: one 10 mm 38 in. in diameter and approximately 300 mm 12 in. in length andthe other 16 mm 58 in. in diameter and approximately 600 mm 24 i

32、n. in length. The 10-mm rod shall be used with paste, grout,and mortar. The 16-mm rod shall be used with concrete.6. Test Specimen6.1 Unless otherwise specified, prepare two test specimens from each batch to be tested simultaneously using duplicate testapparatus. For cement pastes, grouts, and morta

33、rs where all the aggregate will pass through a 4.75-mm (No. 4) sieve, use the100-mm 4-in. mold. For cementitious mixtures containing aggregate that will not all pass through a 4.75-mm sieve, but whichwill all pass the 12.5-mm 12-in. sieve, use the 150-mm 6-in. mold. For concrete mixtures having part

34、icles retained on the12.5-mm 12-in. sieve or larger, use the 300-mm 12-in. mold.7. Calibration7.1 GeneralMinimize any sources of light not required for the tests. Locate the test equipment and specimens on a surfacesubstantially free of vibration during the test. If desired, use a single projected l

35、ight source for both test specimens with duplicatemagnifying lens systems and indicating charts.7.2 Apparatus CalibrationCalibrate the entire apparatus prior to the start of each test. Darken the room, illuminate theprojected light source, and place the dummy test specimens (preferably hardened test

36、 specimens) in the light beam before each ofthe magnifying lens systems. Adjust the location of each test specimen until a sharp, clear image of the indicator ball is producedon the indicating chart. Then reposition the indicating chart so that the indicating ball image falls on the zero line. Since

37、 somemagnifying lens systems result in an inverted display on the indicating charts, note whether an increase in height will be displayedon the indicating chart as a change above or below the 0 (starting) line so that the measurement data obtained during the test isinterpreted correctly. Place a ste

38、el rod of known diameter (see Note 4) horizontally on top of each indicator ball and record theheight of the image it produces on its respective indicating chart. The ratio of the image height to the actual rod diameter is themagnification of the lens system. Moving the projected light source, test

39、specimen, and magnifying lens system toward or awayfrom the indicating chart can change the magnification. Once proper magnification (90 to 110) is obtained, obtained and thedirection of height change displayed is noted, remove the dummy test specimens and do not change the relative locations of the

40、test apparatus during the test.NOTE 4The shank of a 2-mm 116-in. twist drill bit has been found satisfactory for most tests.8. Preparation of Mixtures8.1 GeneralBring all materials to a temperature of 23 6 2.0 C 73 6 3 F before mixing. Other material temperatures shallbe used for this test method wh

41、en specified. Proportion all materials by mass in accordance with the specifications for thecementitious mixtures to be tested.8.2 Mortars, Pastes, and Grouts:8.2.1 Either hand mix or use a suitable mechanical mixer (see Note 5) for a mixing time of 4 min, unless otherwiserecommended by the manufact

42、urer. Place all the mixing water in the mixing bowl prior to introduction of the other materials forthe batch. For mortar materials that are not premixed, the sequence of mixing shall be in accordance with Practice C305.NOTE 5The mechanical mixer described in Practice C305 is a suitable mixer. Howev

43、er, the clearances between paddle and bowl specified in this testmethod are suitable only for mortars made with fine aggregates that are finer than the 850-m (No. 20) sieve. Mortars made with aggregates containingparticles coarser than the 850-m sieve may require special clearances or a different ty

44、pe of paddle to permit the mixer to operate freely and to avoiddamage to the paddle and bowl.8.2.2 Determine the consistency of the mixtures by the flow test in accordance with the applicable provisions of Test MethodC1437. If this procedure is used, the flow after 5 drops of the flow table in 3 s i

45、s 145 or less. A plastic mixture should have a flowof 100 to 125, and a flowable mixture should have a flow above 125 when tested by the preceding modification of Test MethodC109/C109MC1437 but not less than 30 s when tested using the flow-cone procedure of Test Method C939.Afluid mixture shouldhave

46、 a time of efflux of 10 to 30 s when tested by the flow-cone procedure. The water required to produce the specified consistencyshall be determined by the testing of trial batches. Fresh materials shall be used to make each trial. If not specified or recommendedC827/C827M 163otherwise, use sufficient

47、 mixing water to produce a flow of 135 6 5. For premixed mortars or grouts, use the amount of watersuggested by the manufacturer for the intended application. The consistency should be determined and the values recorded for alltests.8.3 ConcreteMix concrete either manually or in a suitable laborator

48、y mixer in accordance with the applicable provisions ofPractice C192/C192M. Determine the consistency of the concrete by the slump test in accordance with the applicable portions ofTest Method C143/C143M, and unless otherwise specified, use sufficient mixing water to produce a slump of 90 6 15 mm 31

49、26 12 in.9. Molding Specimens9.1 Fabricate 100-mm and 150-mm 4-in. and 6-in. specimens by filling the mold in a continuous pouring operation forpourable mixtures or in three layers with consolidation of each layer by tapping the outside of the mold ten times with a 10-mm38-in. diameter rod in the case of mixtures that are not pourable. Fabricate 300-mm 12-in. specimens in accordance withPractice C192/C192M.9.2 Screed off the surface of the test specimen to the top of the mold. In