1、ACI 238.1R-08Reported by ACI Committee 238Report on Measurements ofWorkability and Rheologyof Fresh ConcreteReport on Measurements of Workabilityand Rheology of Fresh ConcreteFirst PrintingFebruary 2008ISBN 978-0-87031-268-7American Concrete InstituteAdvancing concrete knowledgeCopyright by the Amer
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10、Most ACI standards and committee reports are gathered together in the annually revised ACI Manual ofConcrete Practice (MCP).American Concrete Institute38800 Country Club DriveFarmington Hills, MI 48331U.S.A.Phone: 248-848-3700Fax: 248-848-3701www.concrete.orgACI 238.1R-08 was adopted and published F
11、ebruary 2008.Copyright 2008, American Concrete Institute.All rights reserved including rights of reproduction and use in any form or by anymeans, including the making of copies by any photo process, or by electronic ormechanical device, printed, written, or oral, or recording for sound or visual rep
12、roductionor for use in any knowledge or retrieval system or device, unless permission in writingis obtained from the copyright proprietors.238.1R-1ACI Committee Reports, Guides, Manuals, StandardPractices, and Commentaries are intended for guidance inplanning, designing, executing, and inspecting co
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14、nsibility for the stated principles. The Institute shall notbe liable for any loss or damage arising therefrom.Reference to this document shall not be made in contractdocuments. If items found in this document are desired by theArchitect/Engineer to be a part of the contract documents, theyshall be
15、restated in mandatory language for incorporation bythe Architect/Engineer.Report on Measurements of Workabilityand Rheology of Fresh ConcreteReported by ACI Committee 238ACI 238.1R-08This report provides a comprehensive view of workability of fresh concreteand a critical review of the tests availabl
16、e to measure workability andrheological performance of fresh concrete. The report discusses the factorsaffecting the performance of fresh concrete and provides a better under-standing of the issues related to the design of workable concrete, from noflow (zero-slump) to flow like a liquid (self-conso
17、lidating concrete).Keywords: rheological measurements; rheology; workability; workabilitymeasurements.CONTENTSChapter 1Introduction, p. 238.1R-2Chapter 2Rheological terms related to concrete, p. 238.1R-22.1Notation2.2Definitions2.3Shear flow curvesChapter 3Test methods, p. 238.1R-43.1Introduction3.2
18、Principles of measurements3.3Description of existing test methods3.4Criteria for evaluating test methodsChapter 4Factors affecting workability of concrete, p. 238.1R-444.1Introduction4.2Effects of cement4.3Effects of water content4.4Effects of aggregates4.5Effects of chemical admixtures4.6Effects of
19、 supplementary cementitious materials4.7Effect of mixing procedure4.8Effects of temperature and timeChapter 5Examples of using workability test methods, p. 238.1R-525.1Use of gyratory tester to measure workability of no-slump concrete5.2Using rheological measurements to solve problemwith flooring gr
20、outs5.3Measuring batch-to-batch consistency of self-consolidating concrete5.4Troubleshooting self-consolidating concrete mixtures5.5Use of rheological approach to optimize cement-based grout for underwater crack injection ofdamaged bridgeChapter 6References, p. 238.1R-646.1Referenced standards and r
21、eports6.2Cited referencesSofiane Amziane Neil J. Crockett Kamal H. Khayat Konstantin SobolevLynn E. Brower Peter L. Domone Moncef L. Nehdi Mohammed SonebiVan K. Bui Sinan Turhan Erdogan H. Celik Ozyildirim Jussara TanesiSamir E. Chidiac David W. Fowler Vincent Picandet Kejin WangPeter A. Claisse Aul
22、is KappiOther contributors (non-members): C. Cornman, A. Mekhatria, J. Daczko, A. Jeknavorian, and E. Nordenswan.Chiara F. FerrarisChairEric KoehlerSecretary238.1R-2 ACI COMMITTEE REPORTCHAPTER 1INTRODUCTIONFresh concrete properties are related to the properties ofhardened concrete. Poor placement o
23、r consolidation leads tohoneycombing, which reduces compressive strength andincreases permeability, thereby leaving the concrete open tochemical attack. Nevertheless, fresh concrete properties arenot always properly measured or predicted. The mainmeasurement of workability, the slump test, is not al
24、waysapplicable; at the same slump value, two concretes mayexhibit different workabilities. On the other hand, hundredsof tests were designed over the years to measure the work-ability of concrete. The question is how to select the propertest for the application at hand and how to interpret theresult
25、s obtained to predict the performance of the concrete inthe field in the fresh state.To address these questions, it is necessary first to defineworkability in terms of fundamental physical entities, asdescribed in the science of rheology. Therefore, this reporthas four main parts:1. Definitions rela
26、ted to rheology and workability;2. Critical review of the tests available to measure theworkability and rheological performance of fresh concrete;3. Discussion of the factors affecting the performance offresh concrete; and4. Examples that illustrate the application of rheology andmaterial science to
27、 predict or improve the performance offresh concrete in the field.This report presents issues related to the design of a workableconcrete for an application. Workable can mean no flow(zero-slump) or flow like a liquid (self-consolidatingconcrete SCC), depending on the application.CHAPTER 2RHEOLOGICA
28、L TERMSRELATED TO CONCRETE2.1Notationc = insignificant constantg=gravityh = height of slump cone moldK = consistencyn=power index representing deviation from Newtonianbehaviors = slump, mmV = volume of slump cone = time-dependent parameter = constant= shear rate = concentration of solidsm= maximum p
29、acking density = viscosity of suspension = intrinsic viscositypl= plastic viscosityr= relative viscositys= viscosity of the matrix= apparent viscosity at very high shear rate = density, kg/m3 = shear stress, Pao= yield stress not BinghamB= Bingham yield stress2.2DefinitionsDefinitions related to con
30、crete rheology and flow are listedin this section. These definitions were taken from the Cementand Concrete Terminology page of the ACI website(http:/www.concrete.org/Technical/CCT/FlashHelp/ACI_Terminology.htm). Several of these definitions werebased on Hackley and Ferraris (2001), which presentsco
31、ncrete rheology in the wider context of concentratedparticle systems.Bingham model = B+ pl= 0 for Confined flow tests (3.3.1.1)Compaction factor test (3.3.1.1.1)Free orifice test (Orimet test) (3.3.1.1.2)K-slump tester (3.3.1.1.3)Free flow tests (3.3.1.2)Cone penetration test (3.3.1.2.1)Delivery-chu
32、te depth meter (3.3.1.2.2)Delivery-chute torque meter (3.3.1.2.3)Flow trough test (3.3.1.2.4)Kelly ball test (3.3.1.2.5)Modified slump test (3.3.1.2.6)Moving sphere viscometer (3.3.1.2.7)Ring penetration test (3.3.1.2.8)SLump Rate Machine (SLRM) (3.3.1.2.9)Slump test (3.3.1.2.10)Surface settlement t
33、est (3.3.1.2.11)Vibration tests (3.3.1.3)Angles flow box test (3.3.1.3.1)Compaction test (3.3.1.3.2)Flow table test (DIN flow table) (3.3.1.3.3)Inverted slump cone test (3.3.1.3.4)LCL flow test (3.3.1.3.5)Powers remolding test (3.3.1.3.6)Settlement column segregation test (3.3.1.3.7)Thaulow tester (
34、3.3.1.3.8)Vebe consistometer (3.3.1.3.9)Vertical pipe apparatus (3.3.1.3.10)Vibrating slope apparatus (3.3.1.3.11)Vibratory flow meter (3.3.1.3.12)Vibropenetrator (3.3.1.3.13)Wigmore consistometer (3.3.1.3.14)Rotational rheometers (3.3.1.4)Bertta apparatus (3.3.1.4.1)BML viscometer (3.3.1.4.2)BTRHEO
35、M rheometer (3.3.1.4.3)CEMAGREF-IMG (3.3.1.4.4)Concrete truck mixer as rheometer (3.3.1.4.5)Consolis Rheomixer(3.3.1.4.6)CONVI Visco-Probe (3.3.1.4.7)FHPCM (3.3.1.4.8)Fresh concrete tester 101 (FCT 101) (3.3.1.4.9)ICAR rheometer (3.3.1.4.10)IBB rheometer (3.3.1.4.11)Mixer devices (3.3.1.4.12)Powers
36、and Wiler plastometer (3.3.1.4.13)Rheometer-4SCC (3.3.1.4.14)Soil direct shear test (3.3.1.4.15)Tattersall two-point device (3.3.1.4.16)Tests for very high yield-stress concrete (3.3.1.5)Intensive compaction test (3.3.1.5.1)Kango hammer test (3.3.1.5.2)Proctor test (3.3.1.5.3)Other test methods (3.3
37、.1.6)Multiple single-point tests (3.3.1.6.1)Soil triaxial test (3.3.1.6.2)System and method for controlling concrete production (3.3.1.6.3)Trowel test (3.3.1.6.4)Confined flow testsFill box test (3.3.2.2)L-box test (3.3.2.4)Simulated soffit test (3.3.2.6)U-box test (3.3.2.8)V-funnel test (3.3.2.9)Fr
38、ee flow testsJ-ring test (3.3.2.3)Slump flow test (3.3.2.7)Stability testsColumn segregation test (3.3.2.1)Penetration test for Segregation (3.3.2.5)Wet sieving stability test (3.3.2.10)Flow cone and marsh cone tests (3.3.3.1)Lombardi plate (3.3.3.2)Mini-flow test (3.3.3.3)Mini-slump test (3.3.3.4)R
39、otational rheometersTurning tube viscometer (3.3.3.5)Vicat needle test (3.3.3.6)ViscoCorder (3.3.3.7)Wuerpel device (3.3.3.8)*Tests placed in alphabetical order.MEASUREMENTS OF WORKABILITY AND RHEOLOGY OF FRESH CONCRETE 238.1R-7The three confined flow tests presented herein are simpleto perform and
40、provide additional information that the slumptest does not provide. The tests, however, are more complexthan the slump testthough much less complex than rotationalrheometersand are not widely used.3.3.1.1.1 Compaction factor test (or consolidatingfactor test)The compaction factor test (Powers 1968;N
41、eville 1996; Bartos 1992; Bartos et al. 2002) measures thedegree of compaction resulting from the application of astandard amount of work. The test was developed in Britainin the late 1940s and was standardized as BS 1881-103(British Standards Institute 1993).The commercially available apparatus con
42、sists of a rigidframe that supports two conical hoppers vertically alignedabove each other and mounted above a cylinder, as shown inFig. 3.1. The top hopper is slightly larger than the bottomhopper, while the cylinder is smaller in volume than bothhoppers. To perform the test, the top hopper is fill
43、ed withconcrete, but is not compacted. The door on the bottom of thetop hopper is opened, and the concrete is allowed to drop intothe lower hopper. Once all of the concrete has fallen from thetop hopper, the door on the lower hopper is opened to allowthe concrete to fall to the bottom cylinder. A ta
44、mping rod canbe used to force especially cohesive concretes through thehoppers. The excess concrete is carefully struck off the topof the cylinder, and the mass of the concrete in the cylinderis recorded. This mass is compared with the mass of fullycompacted concrete in the same cylinder achieved wi
45、th handrodding or vibration. The compaction factor is defined as theratio of the mass of the concrete compacted in the compactionfactor apparatus to the mass of the fully compacted concrete.The previously described standard test apparatus is appro-priate for concretes with aggregate sizes of up to 2
46、0 mm(3/4 in.). A larger apparatus is available for concretes withmaximum aggregate sizes of up to 40 mm (1-1/2 in.).The results of the compaction factor test can be correlatedto slump, although the relationship is not linear. Wilby(1991) relates the results of the compaction factor test toslump and
47、a general description of workability (Table 3.5).The compaction factor test has been used more widely inEurope than in the United States, although the overall use ofthe test is declining. The test has typically been used inprecast operations and at large construction sites. Comparedwith the slump te
48、st, the apparatus is bulky, and a balance isrequired to perform measurements. In addition to thesepractical drawbacks, the test has several flaws that reducethe accuracy of the results. Some of the work imparted intothe concrete is lost in friction between the hoppers and theconcrete. The magnitude
49、of this friction varies betweendifferent concrete mixtures, and may not be reflective offield conditions. Further, the compaction factor test does notuse vibration, which is the main compaction method used inthe field (Bartos 1992).Advantages:The compaction factor test gives more information (thatis, about compactability) than the slump test; andThe test is a dynamic test and thus is more appropriatethan static tests for highly thixotropic concrete mixtures.Dis
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