1、544.1R-1ACI 544.1R-96 became effective November 18, 1996. This report supersedes ACI544.1R-82(86).Copyright 1997, 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
2、 ormechanical device, printed, written, or oral, or recording for sound or visual reproduc-tion or for use in any knowledge or retrieval system or device, unless permission inwriting is obtained from the copyright proprietors.ACI Committee Reports, Guides, and Commentaries areintended for guidance i
3、n planning, designing, executing, andinspecting construction. This document is intended for the useof individuals who are competent to evaluate the significanceand limitations of its content and recommendations and whowill accept responsibility for the application of the material itcontains. The Ame
4、rican Concrete Institute disclaims any andall responsibility for the stated principles. The Institute shallnot be 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
5、 be a part of the contract documents, theyshall be restated in mandatory language for incorporation bythe Architect/Engineer.The report prepared by ACI Committee 544 on Fiber Reinforced Concrete(FRC) is a comprehensive review of all types of FRC. It includes fundamentalprinciples of FRC, a glossary
6、of terms, a description of fiber types, manufac-turing methods, mix proportioning and mixing methods, installation prac-tices, physical properties, durability, design considerations, applications,and research needs. The report is broken into five chapters: Introduction,Steel FRC, Glass FRC, Syntheti
7、c FRC, and Natural FRC.Fiber reinforced concrete (FRC) is concrete made primarily of hydrauliccements, aggregates, and discrete reinforcing fibers. Fibers suitable for rein-forcing concrete have been produced from steel, glass, and organic polymers(synthetic fibers). Naturally occurring asbestos fib
8、ers and vegetable fibers,such as sisal and jute, are also used for reinforcement. The concrete matricesmay be mortars, normally proportioned mixes, or mixes specifically formu-lated for a particular application. Generally, the length and diameter of thefibers used for FRC do not exceed 3 in. (76 mm)
9、 and 0.04 in. (1 mm), respec-tively. The report is written so that the reader may gain an overview of theproperty enhancements of FRC and the applications for each general cate-gory of fiber type (steel, glass, synthetic, and natural fibers).Brittle materials are considered to have no significant po
10、st-crackingductility. Fibrous composites have been and are being developed to provideimproved mechanical properties to otherwise brittle materials. Whensubjected to tension, these unreinforced brittle matrices initially deform elas-tically. The elastic response is followed by microcracking, localize
11、d macroc-racking, and finally fracture. Introduction of fibers into the concrete results inpost-elastic property changes that range from subtle to substantial,depending upon a number of factors, including matrix strength, fiber type,fiber modulus, fiber aspect ratio, fiber strength, fiber surface bo
12、nding char-Report on Fiber Reinforced ConcreteReported by ACI Committee 544James I. Daniel*ChairmanVellore S. GopalaratnamSecretaryMelvyn A. GalinatMembership SecretaryShuaib H. Ahmad George C. Hoff Morris SchupackM. Arockiasamy Roop L. Jindal Surendra P. ShahP. N. Balaguru*Colin D. Johnston George
13、D. SmithHiram P. Ball, Jr. Mark A. Leppert Philip A. SmithNemkumar Banthia Clifford N. MacDonald Parvis SoroushianGordon B. Batson Pritpal S. Mangat James D. SpeakmanM. Ziad Bayasi Henry N. Marsh, Jr.David J. StevensMarvin E. Criswell Nicholas C. Mitchell R. N. SwamyDaniel P. Dorfmueller Henry J. Mo
14、lloyPeter C. TatnallMarsha Feldstein D. R. Morgan Ben L. TilsenAntonio V. Fernandez A. E. Naaman George J. VentaSidney Freedman Antonio Nanni Gary L. VondranDavid M. Gale Seth L. Pearlman*Methi WecharatanaAntonio J. Guerra*Max L. Porter Spencer T. WuLloyd E. Hackman V. Ramakrishnan Robert C. Zellers
15、C. Geoffrey Hampson Ken Rear Ronald F. ZolloM. Nadim Hassoun D. V. ReddyCarol D. Hays Ernest K. Schrader*Cochairmen, State-of-the-Art Subcommittee; responsible for preparing Chapter 1 and coordinating the entire report.Chairman, Steel Fiber Reinforced Concrete Subcommittee; responsible for preparing
16、 Chapter 2.Chairman, Glass Fiber Reinforced Concrete Subcommittee; responsible for perparing Chapter 3.Chairman, Synthetic Fiber Reinforced Concrete Subcommittee; responsible for preparing Chapter 4.*Cochairmen, Natural Fiber Reinforced Concrete Subcommittee; responsible for preparing Chapter 5.Chai
17、rman, Editorial Subcommittee; responsible for reviewing and final editing the entire report.Previous Chairman of Committee 544; responsible for overseeing the development of the majority of this State-of-the-Art Report.Previous Chairman of Glass Fiber Reinforced Concrete Subcommittee; responsible fo
18、r overseeing the development of much of Chapter 3.ACI 544.1R-96(Reapproved 2009)544.1R-2 ACI COMMITTEE REPORTacteristics, fiber content, fiber orientation, and aggregate size effects. Formany practical applications, the matrix first-crack strength is not increased.In these cases, the most significan
19、t enhancement from the fibers is the post-cracking composite response. This is most commonly evaluated andcontrolled through toughness testing (such as measurement of the area underthe load-deformation curve).If properly engineered, one of the greatest benefits to be gained by using fiberreinforceme
20、nt is improved long-term serviceability of the structure orproduct. Serviceability is the ability of the specific structure or part to main-tain its strength and integrity and to provide its designed function over itsintended service life.One aspect of serviceability that can be enhanced by the use
21、of fibers iscontrol of cracking. Fibers can prevent the occurrence of large crack widthsthat are either unsightly or permit water and contaminants to enter, causingcorrosion of reinforcing steel or potential deterioration of concrete 1.1. Inaddition to crack control and serviceability benefits, use
22、of fibers at highvolume percentages (5 to 10 percent or higher with special production tech-niques) can substantially increase the matrix tensile strength 1.1.CONTENTSChapter 1Introduction, pp. 544.1R-21.1Historical aspects1.2Fiber reinforced versus conventionally-reinforcedconcrete1.3Discussion of
23、fiber types1.4Production aspects1.5Developing technologies1.6Applications1.7Glossary1.8Recommended references1.9Cited referencesChapter 2Steel fiber reinforced concrete (SFRC), pp. 544.1R-72.1Introduction2.2Physical properties2.3Preparation technologies2.4Theoretical modeling2.5Design considerations
24、2.6Applications2.7Research needs2.8Cited referencesChapter 3Glass fiber reinforced concrete (GFRC), pp. 544.1R-233.1Introduction3.2Fabrication of GFRC material3.3Properties of GFRC3.4Long-term performance of GFRC3.5Freeze-thaw durability3.6Design procedures3.7Applications of GFRC3.8GFRC panel manufa
25、cture3.9Surface bonding3.10Research recommendations3.11Cited referencesChapter 4Synthetic fiber reinforced concrete (SNFRC), pp. 544.1R-384.1Introduction4.2Physical and chemical properties of commerciallyavailable synthetic fibers4.3Properties of SNFRC4.4Composite production technologies4.5Fiber par
26、ameters4.6Applications of SNFRC4.7Research needs4.8Cited referencesChapter 5Natural fiber reinforced concrete (NFRC), pp. 544.1R-565.1Introduction5.2Natural fibers5.3Unprocessed natural fiber reinforced concrete5.4Processed natural fiber reinforced concrete5.5Practical applications5.6Summary5.7Resea
27、rch needs5.8Cited referencesCHAPTER 1INTRODUCTION1.1Historical aspectsSince ancient times, fibers have been used to reinforcebrittle materials. Straw was used to reinforce sun-bakedbricks, and horsehair was used to reinforce masonry mortarand plaster. A pueblo house built around 1540, believed to be
28、the oldest house in the U.S., is constructed of sun-bakedadobe reinforced with straw. In more recent times, largescale commercial use of asbestos fibers in a cement pastematrix began with the invention of the Hatschek process in1898. Asbestos cement construction products are widelyused throughout th
29、e world today. However, primarily due tohealth hazards associated with asbestos fibers, alternate fibertypes were introduced throughout the 1960s and 1970s.In modern times, a wide range of engineering materials(including ceramics, plastics, cement, and gypsum products)incorporate fibers to enhance c
30、omposite properties. Theenhanced properties include tensile strength, compressivestrength, elastic modulus, crack resistance, crack control, dura-bility, fatigue life, resistance to impact and abrasion, shrinkage,expansion, thermal characteristics, and fire resistance.Experimental trials and patents
31、 involving the use ofdiscontinuous steel reinforcing elementssuch as nails,wire segments, and metal chipsto improve the propertiesof concrete date from 1910 1.2. During the early 1960s inthe United States, the first major investigation was made toevaluate the potential of steel fibers as a reinforce
32、ment forconcrete 1.3. Since then, a substantial amount of research,development, experimentation, and industrial application ofsteel fiber reinforced concrete has occurred.Use of glass fibers in concrete was first attempted in theUSSR in the late 1950s 1.4. It was quickly established thatordinary gla
33、ss fibers, such as borosilicate E-glass fibers, areattacked and eventually destroyed by the alkali in the cementpaste. Considerable development work was directed towardsproducing a form of alkali-resistant glass fibers containingzirconia 1.5. This led to a considerable number of commer-cialized prod
34、ucts. The largest use of glass fiber reinforcedFIBER REINFORCED CONCRETE 544.1R-3concrete in the U.S. is currently for the production of exteriorarchitectural cladding panels.Initial attempts at using synthetic fibers (nylon, polypro-pylene) were not as successful as those using glass or steelfibers
35、 1.6, 1.7. However, better understanding of theconcepts behind fiber reinforcement, new methods of fabri-cation, and new types of organic fibers have led researchersto conclude that both synthetic and natural fibers cansuccessfully reinforce concrete 1.8, 1.9.Considerable research, development, and
36、applications ofFRC are taking place throughout the world. Industry interestand potential business opportunities are evidenced bycontinued new developments in fiber reinforced constructionmaterials. These new developments are reported in numerousresearch papers, international symposia, and state-of-t
37、he-artreports issued by professional societies. The ACI Committee544 published a state-of-the-art report in 1973 1.10.RILEMs committee on fiber reinforced cement compositeshas also published a report 1.11. A Recommended Practiceand a Quality Control Manual for manufacture of glass fiberreinforced co
38、ncrete panels and products have been publishedby the Precast/Prestressed Concrete Institute 1.12, 1.13.Three recent symposium proceedings provide a good summaryof the recent developments of FRC 1.14, 1.15, 1.16.Specific discussions of the historical developments ofFRC with various fiber types are in
39、cluded in Chapters 2through 5.1.2Fiber-reinforced versus conventionally reinforced concreteUnreinforced concrete has a low tensile strength and a lowstrain capacity at fracture. These shortcomings are tradition-ally overcome by adding reinforcing bars or prestressingsteel. Reinforcing steel is conti
40、nuous and is specificallylocated in the structure to optimize performance. Fibers arediscontinuous and are generally distributed randomlythroughout the concrete matrix. Although not currentlyaddressed by ACI Committee 318, fibers are being used instructural applications with conventional reinforceme
41、nt.Because of the flexibility in methods of fabrication, fiberreinforced concrete can be an economic and useful construc-tion material. For example, thin (1/2 to 3/4 in. 13 to 20 mmthick), precast glass fiber reinforced concrete architecturalcladding panels are economically viable in the U.S. andEur
42、ope. In slabs on grade, mining, tunneling, and excavationsupport applications, steel and synthetic fiber reinforcedconcrete and shotcrete have been used in lieu of welded wirefabric reinforcement.1.3Discussion of fiber typesThere are numerous fiber types available for commercial andexperimental use.
43、 The basic fiber categories are steel, glass,synthetic, and natural fiber materials. Specific descriptions ofthese fiber types are included in Chapters 2 through 5.1.4Production aspectsFor identical concrete mixtures, addition of fibers willresult in a loss of slump as measured by ASTM C 143. Thislo
44、ss is magnified as the aspect ratio of the fiber or the quan-tity of fibers added increases. However, this slump loss doesnot necessarily mean that there is a corresponding loss ofworkability, especially when vibration is used during place-ment. Since slump is not an appropriate measure of work-abil
45、ity, it is recommended that the inverted slump cone test(ASTM C 995) or the Vebe Test (BS 1881) be used to eval-uate the workability of fresh FRC mixtures.For conventionally mixed steel fiber reinforced concrete(SFRC), high aspect ratio fibers are more effective inimproving the post-peak performance
46、 because of their highresistance to pullout from the matrix. A detrimental effect ofusing high aspect ratio fibers is the potential for balling of thefibers during mixing. Techniques for retaining high pulloutresistance while reducing fiber aspect ratio include enlargingor hooking the ends of the fi
47、bers, roughening their surfacetexture, or crimping to produce a wavy rather than straightfiber profile. Detailed descriptions of production methodsfor SFRC are found in Chapter 2.Glass fiber reinforced concretes (GFRC) are produced byeither the spray-up process or the premix process. In thespray-up
48、process, glass fibers are chopped and simulta-neously deposited with a sprayed cement/sand slurry ontoforms producing relatively thin panels ranging from 1/2 to3/4 in. (13 to 20 mm) thick. In the premix process, a wet-mixcement-aggregate-glass fiber mortar or concrete is cast,press molded, extruded,
49、 vibrated, or slip formed. Glass fibermortar mixes are also produced for surface bonding,spraying, or shotcreting. Specific GFRC production technol-ogies are described in Chapter 3.Synthetic fiber reinforced concretes (SNFRC) are gener-ally mixed in batch processes. However, some pre-packageddry mixtures have been used. Flat sheet products that arepressed, extruded, or vacuum dewatered have also beenproduced. Long fibers are more effective in improving post-peak performance, but balling ma
