ACI 232 3R-2014 Report on High-Volume Fly Ash Concrete for Structural Applications.pdf

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1、Report on High-Volume Fly Ash Concrete for Structural ApplicationsReported by ACI Committee 232ACI 232.3R-14First PrintingOctober 2014ISBN: 978-0-87031-946-4Report on High-Volume Fly Ash Concrete for Structural ApplicationsCopyright by the American Concrete Institute, Farmington Hills, MI. All right

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9、egulations, including but not limited to, United States Occupational Safety and Health Administration (OSHA) health and safety standards.Participation by governmental representatives in the work of the American Concrete Institute and in the development of Institute standards does not constitute gove

10、rnmental endorsement of ACI or the standards that it develops.Order information: ACI documents are available in print, by download, on CD-ROM, through electronic subscription, or reprint and may be obtained by contacting ACI.Most ACI standards and committee reports are gathered together in the annua

11、lly revised ACI Manual of Concrete Practice (MCP).American Concrete Institute38800 Country Club DriveFarmington Hills, MI 48331Phone: +1.248.848.3700Fax: +1.248.848.3701www.concrete.orgThis report presents technical information to support the use of high-volume fly ash concrete for structural applic

12、ations. The advantages and limitations of high-volume fly ash concrete are discussed, and the characteristics of the fresh and hardened mate-rials and the durability of the material to various aggressive envi-ronments are covered. Field applications are presented along with sustainability features.K

13、eywords: alkali-silica reaction; compressive strength; corrosion of reinforcement; cracking; deicing salts; fly ash; heat of hydration; mixture proportions; modulus of elasticity; shrinkage; sulfate attack; sustainability; tensile strength.CONTENTSCHAPTER 1GENERAL, p. 21.1Introduction, p. 21.2Signif

14、icance, p. 21.3Historical background, p. 21.4Sustainability, p. 31.5Classification of HVFA concrete, p. 41.6Types of fly ash and portland cement, p. 41.7Codes and specifications, p. 51.8In-place strength, p. 5CHAPTER 2DEFINITIONS, p. 5CHAPTER 3CHARACTERISTICS OF FRESH HVFA CONCRETE, p. 53.1Materials

15、 and mixture proportions, p. 53.2Slump and workability, p. 63.3Setting time, p. 63.4Heat of hydration, p. 63.5Plastic shrinkage cracks, p. 7CHAPTER 4CHARACTERISTICS OF HARDENED HVFA CONCRETE, p. 74.1Compressive strength, p. 74.2Tensile strength, p. 94.3Modulus of elasticity, p. 94.4Shrinkage and cre

16、ep, p. 10Karthik H. Obla*, ChairRobert E. Neal, Vice ChairMichael D. A. Thomas*, Vice ChairLawrence L. Sutter, SecretaryACI 232.3R-14Report on High-Volume Fly Ash Concrete for Structural ApplicationsReported by ACI Committee 232Thomas H. AdamsGregory S. BargerJames C. BlankenshipJulie K. Buffenbarge

17、rRamon L. CarrasquilloBarry A. DescheneauxJonathan E. DongellJohn M. FoxThomas M. GreeneHarvey H. HaynesJames K. HicksR. Doug HootonMorris HuffmanJames S. JensenTilghman H. KeiperSteven H. KosmatkaAdrian Marc NacamuliBruce W. Ramme*Steve RatchyeMichael D. SerraAva ShypulaBoris Y. SteinOscar TavaresP

18、aul J. TikalskyThomas J. Van DamCraig R. WallaceOrville R. Werner IIConsulting MembersMark A. BuryJames E. CookDean M. GoldenWilliam HalczakG. Terry Harris, Sr.Jan R. PrusinskiHarry C. RoofDella M. Roy*Task group member who participated in preparing this report.Lead task group member.ACI Committee R

19、eports, Guides, and Commentaries are intended for guidance in planning, designing, executing, and inspecting construction. This document is intended for the use of individuals who are competent to evaluate the significance and limitations of its content and recommendations and who will accept respon

20、sibility for the application of the material it contains. The American Concrete Institute disclaims any and all responsibility for the stated principles. The Institute shall not be liable for any loss or damage arising therefrom.Reference to this document shall not be made in contract documents. If

21、items found in this document are desired by the Architect/Engineer to be a part of the contract documents, they shall be restated in mandatory language for incorporation by the Architect/Engineer.ACI 232.3R-14 was adopted and published October 2014.Copyright 2014, American Concrete Institute.All rig

22、hts reserved including rights of reproduction and use in any form or by any means, including the making of copies by any photo process, or by electronic or mechanical device, printed, written, or oral, or recording for sound or visual reproduc-tion or for use in any knowledge or retrieval system or

23、device, unless permission in writing is obtained from the copyright proprietors.1CHAPTER 5DURABILITY, p. 105.1Cracking, p. 105.2Permeability, p. 105.3Alkali-silica reaction, p. 115.4Sulfate attack, p. 115.5Corrosion of reinforcing steel, p. 115.6Freezing and thawing, p. 125.7Deicing salts, p. 125.8P

24、hysical salt attack, p. 135.9Carbonation, p. 13CHAPTER 6FIELD APPLICATIONS, p. 136.1General, p. 136.2Placement and consolidation, p. 146.3Finishing and curing, p. 146.4Strength development and schedule, p. 146.5Cold weather placement, p. 146.6Hot weather placement, p. 156.7100 percent Class C fly as

25、h concrete, p. 156.8Barriers to the use of HVFA concrete, p. 15CHAPTER 7HVFA CONCRETE AND SUSTAINABLE CONSTRUCTION, p. 157.1Sustainability rating systems, p. 15CHAPTER 8REFERENCES, p. 16Authored documents, p. 16CHAPTER 1GENERAL1.1IntroductionHigh-volume fly ash (HVFA) concrete is a sustainable const

26、ruction material when proportioned properly and used in appropriate construction applications. This report summa-rizes published data on the composition and properties of the material, such as workability, strength, and durability. The report affirms the viability of HVFA concrete for structural app

27、lications and discusses construction issues.HVFA concrete is defined as having a large replacement by mass of portland cement with fly ash. Malhotra (1986) defined HVFA concrete as concrete containing 50 percent or more fly ash by mass of total cementitious materials, and Ramme and Tharaniyil (2000)

28、 defined it as concrete with 37 percent or more fly ash by mass as total cementitious materials.Naik and Ramme (1985) tested HVFA concrete using ASTM C618 Class C fly ash mixtures and having water-cementitious material ratios (w/cm) ranging from 0.42 to 0.57, without the use of high-range water-redu

29、cing admix-tures. In 1986, however, a significant research program was initiated to explore the possibility of HVFA concrete attaining compressive strengths of 7250 psi (50 MPa) or higher for structural applications (Malhotra 1986). This research used concrete mixtures containing ASTM C618 Class F f

30、ly ash, 0.30 w/cm, and high-range water-reducing admixtures. The results of this work showed the potential of HVFA concrete as a sustainable material with workability, strength, and durability exceeding that of conventional port-land-cement concrete having similar cementitious content. Summaries of

31、the results on HVFA concrete using Class F fly ash are given by Malhotra (1992, 2002), Bilodeau and Malhotra (2000), and Malhotra and Mehta (2012).Low-strength HVFA concrete mixtures are not covered herein. In this document, HVFA concretes that have minimum specified compressive strengths of 2500 ps

32、i (17 MPa) are discussed.1.2SignificanceThis report provides background information and tech-nical data to support the use of HVFA concrete for struc-tural applications. From a sustainability standpoint, HVFA concrete not only significantly reduces consumption of port-land cement, but also results i

33、n a concrete of superior quality in many aspects when compared with that of conventional concrete in regard to workability, strength, and durability. In addition, this technology is currently available for wide-scale implementation and is backed by more than 25 years of field usage and test results.

34、1.3Historical backgroundIn 1937, Davis et al. (1937) experimented with concretes containing fly ash of up to 50 percent replacement by mass of portland cement. They concluded that the use of HVFA in mass concrete has definite advantages, such as lower temperature rise due to heat of hydration and le

35、ss risk due to thermal cracking. These findings were applied in the first significant use of fly ash in concrete for Hungry Horse Dam in Montana, which was built from 1948-1952. In those early years, concretes using high levels of fly ash were limited to mass concrete structures. The incentive was t

36、o reduce the adiabatic temperature rise resulting from heat of hydration of portland cement. Compressive strengths were generally low at early ages with strengths increasing from 1450 to 2900 psi (10 to 20 MPa) at 90 days.In the late 1970s, the use of fly ash at 60 to 70 percent by mass of cementiti

37、ous material was found to significantly improve the performance of roller-compacted concrete (Dunstan 1983). The Upper Stillwater Dam in Utah was constructed using this material in early 1980. During a full-scale trial test of roller-compacted concrete in 1978, a slipformed vertical facing element w

38、as constructed using concrete containing approximately 40 percent fly ash by mass (Dunstan 1983). Subsequently, the first major place-ment of concrete containing over 50 percent fly ash replace-ment by mass of portland cement was in 1981, where the concrete was consolidated by immersion vibration fo

39、r the construction of access roads at the Didcot Power Station in Oxfordshire, UK (Dunstan 1983). Success in this project led to use of the material in other applications between 1982 and 1984: foundation and retaining walls for an oil tank storage area (51 percent fly ash by mass), marine slipway (

40、52 percent), sewage treatment works (54 percent), and concrete viaducts (35 to 65 percent). Five of these structures were evaluated by visual examination and testing of cores approximately 10 years after construction, and were found to be in excellent condition (Dunstan et al. 1992).American Concret

41、e Institute Copyrighted Material www.concrete.org2 REPORT ON HIGH-VOLUME FLY ASH CONCRETE FOR STRUCTURAL APPLICATIONS (ACI 232.3R-14)In the mid-1980s, a number of researchers from different countries embarked on studies of concrete containing 50 percent or more of both Class C and Class F fly ash by

42、 mass (Ghosh and Timusk 1981; Munday et al. 1983; Yuan and Cook 1983; Pistilli and Majko 1984; Haque et al. 1986; Joshi et al. 1986; Nasser and Al-Manaseer 1986, 1987; Papayianni 1986; Ravina and Mehta 1986, 1988; Swamy and Mahmud 1986; Tse et al. 1986; Johnston and Malhotra 1987; Naik and Ramme 198

43、7a; Roselle 1987; Sivasundaram et al. 1987). Limited field application of the material resulted from these studies. Two demonstration projects were conducted by Wisconsin Electric in 1984, however, where 70 percent Class C fly ash by mass was used in concrete for pavement and transformer foundations

44、 (Naik and Ramme 1987b, 1989). Since that time, Wisconsin Electric has constructed a number of pavements using HVFA concrete with success (Naik et al. 1995).In 1985, Malhotra and coworkers at CANMET (Malhotra 1986) began work on HVFA concrete. The focus was on concrete having low water content (190

45、lb/yd3115 kg/m3), low portland cement content (255 lb/yd3155 kg/m3), high Class F fly ash content (55 to 60 percent by mass of cementi-tious materials), and a HRWRA for workability. Compared to conventional portland-cement concrete, HVFA concrete mixtures achieved moderate early-age and high ultimat

46、e strength. In the ensuing years, many significant structures have been built using HVFA concrete based on CANMETs work (Malhotra and Mehta 2012), and today, research data exist from more than 25 years of their field performance.1.4SustainabilityConcrete, by volume, is the most common man-made mater

47、ial in the world. It has a relatively low embodied energy coefficient (ranging from 0.95 to 2.0 MJ/kg) depending on geographical location, technology employed in the manufac-turing process, and methods of manufacture (Alcorn 2001). Concrete contains approximately 7 to 15 percent portland cement by v

48、olume (Kosmatka and Wilson 2011); however, it is energy-intensivecarbon dioxide (CO2) is generated during its manufacturing process. Producing 1 ton (0.9 tonnes) of portland cement typically requires a 3580 MJ of thermal energy (weighted average) and 108 kWh of electric energy (WBCSD 2012). Therefor

49、e, the embodied energy of concrete is a function of the portland cement content of the mixture.Limestone is the principal raw material used to produce portland cement. The main source of CO2emissions from portland cement is due to the decarbonation of the limestone during the manufacturing process. Process emissions, in combination with fossil fuel combustion in the production of portland cement clinker, produce significant amounts of CO2. Approximately 1890 lb (858 kg) of CO2is produced for each metric ton of portland cement cl