ASTM C143 C143M-2015a Standard Test Method for Slump of Hydraulic-Cement Concrete《硅酸盐水泥混凝土坍落度的标准试验方法》.pdf

《ASTM C143 C143M-2015a Standard Test Method for Slump of Hydraulic-Cement Concrete《硅酸盐水泥混凝土坍落度的标准试验方法》.pdf》由会员分享，可在线阅读，更多相关《ASTM C143 C143M-2015a Standard Test Method for Slump of Hydraulic-Cement Concrete《硅酸盐水泥混凝土坍落度的标准试验方法》.pdf（4页珍藏版）》请在麦多课文档分享上搜索。

1、Designation: C143/C143M 15aStandard Test Method forSlump of Hydraulic-Cement Concrete1This standard is issued under the fixed designation C143/C143M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last revision. A numb

2、er 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*1.1 This test method covers determination of slump ofhyd

3、raulic-cement concrete, both in the laboratory and in thefield.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. Within the text, theSI units are shown in brackets. The values stated in eachsystem may not be exact equivalents; therefore, each syst

4、emshall be used independently of the other. Combining valuesfrom the two systems may result in non-conformance with thestandard.1.3 The text of this standard references notes and footnoteswhich provide explanatory material. These notes and footnotes(excluding those in tables and figures) shall not b

5、e consideredas requirements of the standard.1.4 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 determine the applica-bility of regulat

6、ory limitations prior to use. (WarningFreshhydraulic cementitious mixtures are caustic and may causechemical burns to skin and tissue upon prolonged exposure.2)2. Referenced Documents2.1 ASTM Standards:3C31/C31M Practice for Making and Curing Concrete TestSpecimens in the FieldC138/C138M Test Method

7、 for Density (Unit Weight), Yield,and Air Content (Gravimetric) of ConcreteC172 Practice for Sampling Freshly Mixed ConcreteC173/C173M Test Method forAir Content of Freshly MixedConcrete by the Volumetric MethodC231 Test Method for Air Content of Freshly Mixed Con-crete by the Pressure MethodC670 Pr

8、actice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsD638 Test Method for Tensile Properties of Plastics3. Summary of Test Method3.1 A sample of freshly mixed concrete is placed andcompacted by rodding in a mold shaped as the frustum of acone. The mold is rais

9、ed, and the concrete allowed to subside.The vertical distance between the original and displacedposition of the center of the top surface of the concrete ismeasured and reported as the slump of the concrete.4. Significance and Use4.1 This test method is intended to provide the user with aprocedure t

10、o determine slump of plastic hydraulic-cementconcretes.NOTE 1This test method was originally developed to provide atechnique to monitor the consistency of unhardened concrete. Underlaboratory conditions, with strict control of all concrete materials, theslump is generally found to increase proportio

11、nally with the water contentof a given concrete mixture, and thus to be inversely related to concretestrength. Under field conditions, however, such a strength relationship isnot clearly and consistently shown. Care should therefore be taken inrelating slump results obtained under field conditions t

12、o strength.4.2 This test method is considered applicable to plasticconcrete having coarse aggregate up to 112 in. 37.5 mm insize. If the coarse aggregate is larger than 112 in. 37.5 mm insize, the test method is applicable when it is performed on thefraction of concrete passing a 112-in. 37.5-mm sie

13、ve, with thelarger aggregate being removed in accordance with the sectiontitled “Additional Procedure for Large Maximum Size Aggre-gate Concrete” in Practice C172.4.3 This test method is not considered applicable to non-plastic and non-cohesive concrete.NOTE 2Concretes having slumps less than12 in.

14、15 mm may not beadequately plastic and concretes having slumps greater than about 9 in.230 mm may not be adequately cohesive for this test to have signifi-cance. Caution should be exercised in interpreting such results.1This test method is under the jurisdiction of ASTM Committee C09 onConcrete and

15、Concrete Aggregates and is the direct responsibility of SubcommitteeC09.60 on Testing Fresh Concrete.Current edition approved Dec. 15, 2015. Published February 2016. Originallyapproved in 1922. Last previous edition approved in 2015 as C143/C143M 15.DOI: 10.1520/C0143_C0143M-15A2Section on Safety Pr

16、ecautions, Manual of Aggregate and Concrete Testing,Annual Book of ASTM Standards, Vol. 04.02.3For 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 standards Document

17、 Summary page onthe ASTM website.*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 States15. Apparatus5.1 MoldThe test specimen shall be formed in a moldmade of metal or plastic

18、not readily attacked by the cementpaste. The mold shall be sufficiently rigid to maintain thespecified dimensions and tolerances during use, resistant toimpact forces, and shall be non-absorbent. Metal molds shallhave an average thickness of not less than 0.060 in. 1.5 mmwith no individual thickness

19、 measurement less than 0.045 in.1.15 mm. Plastic molds shall be ABS plastic or equivalent(Note 3) with a minimum average wall thickness of 0.125 in.3 mm, with no individual thickness measurement less than0.100 in. 2.5 mm. The manufacturer or supplier shall certifythe materials used in mold construct

20、ion are in compliance withthe requirements of this test method. The mold shall be in theform of the lateral surface of the frustum of a cone with thebase 8 in. 200 mm in diameter, the top 4 in. 100 mm indiameter, and the height 12 in. 300 mm. Individual diametersand heights shall be within 618 in. 3

21、 mm of the prescribeddimensions. The base and the top shall be open and parallel toeach other and at right angles to the axis of the cone. The moldshall be provided with foot pieces and handles similar to thoseshown in Fig. 1. The mold shall be constructed without a seam.The interior of the mold sha

22、ll be relatively smooth and freefrom projections. The mold shall be free from dents,deformation, or adhered mortar. A mold which clamps to anonabsorbent base plate is acceptable instead of the oneillustrated, provided the clamping arrangement is such that itcan be fully released without movement of

23、the mold and thebase is large enough to contain all of the slumped concrete inan acceptable test.NOTE 3ABS (Acrylonitrile Butadiene Styrene) plastic exhibits thefollowing minimum mechanical properties:Tensile modulus of elasticity,at 73 F 23 C320 000 psi 2206 MPaTensile strength (Test Method D638) 5

24、670 psi 39 MPaPercent Elongation at Break,at 73 F 23 C40%5.1.1 Check and record conformance to the molds specifieddimensions when it is purchased or first placed in service andat least annually thereafter. To measure the top diameter,bottom diameter, and height, perform two measurements foreach, app

25、roximately 90 apart, and record the results of eachmeasurement. To verify mold thickness, perform two measure-ments approximately 180 apart at 1 612 in. 25 6 10 mmfrom the top of the mold, two measurements approximately180 apart at 1 612 in. 25 6 10 mm from the bottom of themold, and calculate the a

26、verage of the four measurements.5.2 Tamping RodA round, smooth, straight steel rod, witha58 in. 16 mm 6116 in. 2 mm diameter. The length of thetamping rod shall be at least 4 in. 100 mm greater than thedepth of the mold in which rodding is being performed, but notgreater than 24 in. 600 mm in overal

27、l length (Note 4). The rodshall have the tamping end or both ends rounded to ahemispherical tip of the same diameter as the rod.NOTE 4A rod length of 16 in. 400 mm to 24 in. 600 mm meets therequirements of the following: Practice C31/C31M, Test Method C138/C138M, Test Method C143/C143M, Test Method

28、C173/C173M, and TestMethod C231.5.3 Measuring DeviceA ruler, metal roll-up measuringtape, or similar rigid or semi-rigid length measuring instrumentmarked in increments of14 in. 5 mm or smaller. Theinstruement length shall be at least 12 in. 300 mm.5.4 Scoopof a size large enough so each amount ofco

29、ncrete obtained from the sampling receptacle is representa-tive and small enough so it is not spilled during placement inthe mold.6. Sample6.1 The sample of concrete from which test specimens aremade shall be representative of the entire batch. It shall beobtained in accordance with Practice C172.7.

30、 Procedure7.1 Dampen the mold and place it on a rigid, flat, level,moist, nonabsorbent surface, free of vibration, and that is largeenough to contain all of the slumped concrete. It shall be heldfirmly in place during filling and perimeter cleaning by theoperator standing on the two foot pieces or b

31、y a clampingarrangement to a base plate as described in 5.1. From thesample of concrete obtained in accordance with Section 6,immediately fill the mold in three layers, each approximatelyone third the volume of the mold (See Note 5). Place theconcrete in the mold using the scoop described in 5.4. Mo

32、veDimensional Unitsin.1161812 13318 4812mm 2 3 15 25 75 80 100 200 300FIG. 1 Mold for Slump TestC143/C143M 15a2the scoop around the perimeter of the mold opening to ensurean even distribution of the concrete with minimal segregation.NOTE 5One third of the volume of the slump mold fills it to a depth

33、of 258 in. 70 mm; two thirds of the volume fills it to a depth of 618 in.160 mm.7.2 Rod each layer 25 times uniformly over the crosssection with the rounded end of the rod. For the bottom layer,this will necessitate inclining the rod slightly and makingapproximately half of the strokes near the peri

34、meter, and thenprogressing with vertical strokes spirally toward the center.Rod the bottom layer throughout its depth. For each upperlayer, allow the rod to penetrate through the layer being roddedand into the layer below approximately 1 in. 25 mm.7.3 In filling and rodding the top layer, heap the c

35、oncreteabove the mold before rodding is started. If the roddingoperation results in subsidence of the concrete below the topedge of the mold, add additional concrete to keep an excess ofconcrete above the top of the mold at all times. After the toplayer has been rodded, strike off the surface of the

36、 concrete bymeans of a screeding and rolling motion of the tamping rod.Continue to hold the mold down firmly and remove concretefrom the area surrounding the base of the mold to precludeinterference with the movement of slumping concrete. Removethe mold immediately from the concrete by raising it ca

37、refullyin a vertical direction. Raise the mold a distance of 12 in. 300mm in 5 6 2 s by a steady upward lift with no lateral ortorsional motion. Complete the entire test from the start of thefilling through removal of the mold without interruption andcomplete it within an elapsed time of 212 min.7.4

38、 Immediately measure the slump by determining thevertical difference between the top of the mold and thedisplaced original center of the top surface of the specimen. Ifa decided falling away or shearing off of concrete from oneside or portion of the mass occurs (Note 6), disregard the testand make a

39、 new test on another portion of the sample.NOTE 6If two consecutive tests on a sample of concrete show a fallingaway or shearing off of a portion of the concrete from the mass of thespecimen, the concrete probably lacks necessary plasticity and cohesive-ness for the slump test to be applicable.8. Re

40、port8.1 Report the slump in terms of inches millimetres to thenearest14 in. 5 mm of subsidence of the specimen during thetest.9. Precision and Bias49.1 PrecisionThe estimates of precision for this testmethod are based upon results from tests conducted inFayetteville, Arkansas by 15 technicians from

41、14 laboratoriesrepresenting 3 states. All tests at 3 different slump ranges, from1.0 in. 25 mm to 6.5 in. 160 mm, were performed using oneload of truck-mixed concrete. The concrete was delivered andtested at a low slump, with water then being added and mixedinto the remaining concrete to independent

42、ly produce moderateand finally high-slump concrete. The concrete mixture thatused a No. 67 crushed limestone aggregate and a washed riversand, contained 500 lb of cementitious materials per cubic yard297 kg of cementitious material per cubic metre. The 500 lb227 kg were equally divided between a C15

43、0, Type I/IIcement and a Class C fly ash. A double dosage of a chemicalretarder was used in an attempt to minimize slump losses andmaintain workability of the concrete. Concrete temperaturesranged from 86 to 93 F 30 to 34 C. Slump losses averaged0.68 in. 17 mm during the 20 min required to perform a

44、 seriesof 6 tests at 1 slump range. Testing was performed alternatelyusing metal and plastic molds, which were determined toproduce comparable results. Precision data thus applies to bothmetal and plastic molds. A total of 270 slump tests wereperformed.9.1.1 Inch-Pound SIThe data used to develop the

45、 preci-sion statement were obtained using metric units (millimetres).The precision values shown in inch-pound units are conver-sions from the millimetre measurements, which were recordedto the nearest 1 mm.9.1.2 Measure of VariabilityThe standard deviation wasdetermined to be the most consistent mea

46、sure of variability andwas found to vary with the slump value.9.1.3 Single-Operator PrecisionThe single-operator stan-dard deviation represented by (1s) is shown in Table 1 byaverage slump values. The reported results for the replicatereadings apply to tests conducted by the same operatorperforming

47、successive tests, one immediately following theother.Acceptable results of two properly conducted tests by thesame operator on the same material (Note 7) will not differfrom each other by more than the (d2s) value of the last columnof Table 1 for the appropriate slump value and single-operatorprecis

48、ion.9.1.4 Multilaboratory PrecisionThe multilaboratory stan-dard deviation represented by (1s) is shown in Table 1 byaverage slump values. The reported results for the replicatereadings apply to tests conducted by different operators fromdifferent laboratories performing tests less than 4 min apart.

49、Therefore, acceptable results of two properly conducted slumptests on the same material (Note 7) by two different laborato-ries will not differ from each other by more than the (d2s) valueof the last column of Table 1 for the appropriate slump valueand multilaboratory precision.4The test data used to develop this precision statement were based on testsperformed in September 1997. Supporting data have been filed at ASTM Interna-tional Headquart