1、ACI 549.2R-04Report on Thin Reinforced Cementitious ProductsReported by ACI Committee 549(Reapproved 2013)First PrintingMay 2004Report on Thin Reinforced Cementitious ProductsCopyright by the American Concrete Institute, Farmington Hills, MI. All rights reserved. This material may not be reproduced
2、or copied, in whole or part, in any printed, mechanical, electronic, film, or other distribution and storage media, without the written consent of ACI.The technical committees responsible for ACI committee reports and standards strive to avoid ambiguities, omissions, and errors in these documents. I
3、n spite of these efforts, the users of ACI documents occasionally find information or requirements that may be subject to more than one interpretation or may be incomplete or incorrect. Users who have suggestions for the improvement of ACI documents are requested to contact ACI via the errata websit
4、e at www.concrete.org/committees/errata.asp. Proper use of this document includes periodically checking for errata for the most up-to-date revisions.ACI committee documents are intended for the use of individuals who are competent to evaluate the significance and limitations of its content and recom
5、mendations and who will accept responsibility for the application of the mate-rial it contains. Individuals who use this publication in any way assume all risk and accept total responsibility for the application and use of this information.All information in this publication is provided “as is” with
6、out warranty of any kind, either express or implied, includ-ing but not limited to, the implied warranties of merchantability, fitness for a particular purpose or non-infringement.ACI and its members disclaim liability for damages of any kind, including any special, indirect, incidental, or con-sequ
7、ential damages, including without limitation, lost revenues or lost profits, which may result from the use of this publication.It is the responsibility of the user of this document to establish health and safety practices appropriate to the specific circumstances involved with its use. ACI does not
8、make any representations with regard to health and safety issues and the use of this document. The user must determine the applicability of all regulatory limitations before applying the document and must comply with all applicable laws and regulations, including but not limited to, United States Oc
9、cupational Safety and Health Administration (OSHA) health and safety standards.Participation by governmental representatives in the work of the American Concrete Institute and in the develop-ment of Institute standards does not constitute governmental endorsement of ACI or the standards that it deve
10、lops.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 annually revised ACI Manual of Concrete Practice (MCP).America
11、n Concrete Institute38800 Country Club DriveFarmington Hills, MI 48331U.S.A.Phone: 248-848-3700Fax: 248-848-3701www.concrete.orgISBN 978-0-87031-156-7American Concrete InstituteAdvancing concrete knowledgeACI 549.2R-04 became effective May 19, 2004.Copyright 2004, American Concrete Institute.All rig
12、hts reserved including rights of reproduction and use in an y form or by anymeans, including the making of copies b y any photo process, or by electronic ormechanical device, printed, written, or oral, or recording for sound or visual reproduc-tion or for use in an y knowledge or retrieval system or
13、 device, unless permission inwriting is obtained from the copyright proprietors.ACI Committee Reports, Guides, Standard Practices, andCommentaries are intended for guidance in planning,designing, executing, and inspecting construction. Thisdocument is intended for th e use of individuals who arecomp
14、etent to evaluate the significance and limitations of itscontent and recommendations and who will acceptresponsibility for the application of the material it contains.The American Concrete Inst itute disclaims any and allresponsibility for the stated principles. The Institute shall notbe liable for
15、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 restated in mandatory language for incorporation bythe Architect/Engineer.
16、549.2R-1It is the responsibility of th e user of this document toestablish health and safety practices appropriate to the specificcircumstances involved with its use. ACI does not make anyrepresentations with regard to health and safety issues and theuse of this document. The user must determine the
17、applicability of all regulatory limitations before applying thedocument and must comply w ith all applicable laws andregulations, including but not limited to, United StatesOccupational Safety and Health Administration (OSHA)health and safety standards.Report on Thin ReinforcedCementitious ProductsA
18、CI 549.2R-04Thin reinforced cementitious products offer a useful balance of propertiessuch as strength, toughness, environmental durability, moisture resistance,dimensional stability, fire resistance, esthetics, and ease of handling andinstallation. The growing emphasis on environmental durability a
19、nd fireresistance of cementitious products has led to their increased use worldwide.This report summarizes the current knowledge of reinforcements, manufac-turing methods, engineering properties, and applications of thin reinforcedcementitious products.Keywords: cement-based composites; cement board
20、s; cement panels;composite materials; concrete panels; ductility; durability; engineeringproperties; ferrocement; f iber-reinforced cement-based materials; f ibers;flexural strength; manufacturing methods; mesh reinforcement; reinforcingmaterials; toughness.CONTENTS Chapter 1Introduction, p. 549.2R-
21、2Chapter 2 Reinforcement types and reinforcing mechanisms, p. 549.2R-22.1Discontinuous or discrete reinforcing fibers2.2Continuous reinforcing fibers2.3Reinforcing meshes and mats2.4Reinforcing mechanismsChapter 3Manufacturing methods of thin reinforced cementitious products, p. 549.2R-83.1Hatschek
22、process3.2Simultaneous spray process3.3Premix process3.4Extrusion process3.5Filament winding process3.6Filter-press process3.7Compression molding process3.8Processes with continuous reinforcementReported by ACI Committee 549M. ArockiasamyJohn JonesD. V. ReddyP. N. BalaguruJames R. McConaghySurendra
23、P. ShahHiram P. BallBarzin MobasherYixin ShaoNemkumar BanthiaHenry J. Molloy Anil K. SharmaGordon B. Batson John L. MulderParviz SoroushianJames I. Daniel Antoine E. NaamanNarayan SwamyDavid M. Gale Antonio Nanni George J. VentaGraham T. GilbertNandakumar NatarajanRobert C. ZellersAntonio J. Guerra
24、P. Paramasivam Ronald F. ZolloNeeraj J. BuchChairAshish Dubey*Secretary*Chair of the subcommittee responsible for preparing this report.Co-chair of the subcommittee responsible for preparing this report.Members of the subcommittee responsible for preparing this report.(Reapproved 2013)549.2R-2 ACI C
25、OMMITTEE REPORTChapter 4Engineering properties of thin reinforced cementitious products, p. 549.2R-114.1Natural/cellulose fiber-reinforced products4.2Glass fiber-reinforced products4.3Polymer fiber-reinforced products4.4Carbon fiber-reinforced products4.5Hybrid fiber-reinforced products4.6Mesh/mat-r
26、einforced productsChapter 5Applications of thin reinforced cementitious products, p. 549.2R-185.1Claddings5.2Roofing panels and tiles5.3Substrate panels5.4Ducts, channels, and conduits5.5Linings5.6Pipes and poles5.7Acoustical wall panels and noise barriers5.8Permanent formwork5.9Parapets5.10Landscap
27、ing productsChapter 6Summary, p. 549.2R-24Chapter 7References, p. 549.2R-247.1Referenced standards and reports7.2Cited references7.3Other referencesCHAPTER 1INTRODUCTIONThin reinforced cementitious products are used widelytoday in a variety of applications worldwide. Thin reinforcedcementitious prod
28、ucts are strong, possess superior deform-ability characteristics and enhanced impact and fatigueresistanceproperties that are of great value in many practicalapplications. The aforementioned performance characteristicsresult primarily due to the inclusion of reinforcement in thecementitious matrixes
29、 of these products. In the past, asbestosfibers were the popular form of reinforcement in manufac-turing thin cementitious products because asbestos fibers werewidely available, inexpensive, possessed favorableprocessing characteristics, and provided significantimprovements in strength and toughness
30、 characteristics ofcements and mortars (Table 1.1). The use of asbestos fibers,however, continues to decline rapidly due to the serious healthhazard risk to people involved in handling asbestos fibers andproducts. Consequently, other reinforcement materials havebeen developed to replace asbestos fib
31、ers in thin cementitiouscomposites. These reinforcements are available in differentgeometric configurations such as discrete fibers, continuousfibers, and meshes. The former can be classified as adiscontinuous reinforcement and the latter two as continuousreinforcement. The choice of reinforcement i
32、n terms of materialtype and geometric configuration has a significant influence onthe engineering properties of the resulting thin cementitiousproducts. Thin cementitious products that incorporate metalmeshes as reinforcement are commonly referred to asferrocement. A detailed description of metal ma
33、ts andmeshes and products made thereof is covered in ACI 549Rand not covered in this report. Readers are referred to thatdocument for further information. Thin cementitiousproducts may contain both discontinuous and continuousreinforcements to produce products possessing tailoredperformance characte
34、ristics.Typical applications of thin reinforced cementitious productsinclude exterior faade claddings, architectural elements,roofing panels and tiles, substrate panels for installation oftiles and other finishes, tunnel and sewer linings, cable ducts,permanent formwork, and pipes. Thin reinforced c
35、ementitiousproducts have the ability to satisfy diverse requirements inthese applications, such as strength, deformability, environ-mental durability, moisture resistance, dimensional stability,fire resistance, and rapid and economic construction.As diverse are the reinforcement and the applications
36、 ofthin reinforced cementitious products, so are the manufacturingmethods to produce these products. A variety of cost-effectiveand rapid manufacturing methods have been developed toproduce thin reinforced cementitious products havingdiverse performance characteristics and a range of geometricand ae
37、sthetic features. Popular manufacturing methods of thinreinforced cementitious products are described in this report.Chapter 2 describes different types of reinforcements usedto produce thin reinforced cementitious products. Knownand popular manufacturing methods of thin reinforcedcementitious produ
38、cts are described in Chapter 3. Chapter 4describes the engineering properties of thin reinforcedcementitious products. Finally, different applications of thinreinforced cementitious products are highlighted in Chapter 5.CHAPTER 2REINFORCEMENT TYPESAND REINFORCING MECHANISMSA variety of reinforcement
39、 types are used to manufacturethin reinforced cementitious products today. These reinforce-ments can be broadly classified into three categories:Discontinuous or discrete reinforcing fibers;Continuous reinforcing fibers; andReinforcing meshes.Discrete (discontinuous) fibers are the most popular form
40、of reinforcement used in thin cementitious products.Discrete fibers are made from a variety of materials and areavailable in different lengths and diameters. Examples ofdiscrete fiber reinforcements include natural/cellulosefibers, glass fibers, polymer (polyvinyl alcohol and polypro-pylene) fibers,
41、 and carbon fibers. Continuous reinforcing fibersmade from materials such as glass and polymers have alsobeen used to manufacture thin cementitious products.Table 1.1Mechanical properties of cement paste, cement mortar, and asbestos cement (Studinka 1989; Hannant 1978)Material typePropertyFlexural s
42、trength, MPaTensile strength, MPaElasticmodulus, GPaTensile strain at failure, %Cement paste 7 to 8 3 to 6 15 0.01 to 0.05Cement mortar 2 to 4 25 to 35 0.005 to 0.015Asbestos cement30 to 40 17 to 20 28 to 35 0.40 to 0.50THIN REINFORCED CEMENTITIOUS PRODUCTS 549.2R-3Meshes are yet another form of rei
43、nforcement that arebecoming increasingly popular in thin cementitious products.The performance characteristics of thin reinforced cementitiousproducts depend significantly on the type of reinforcement used.2.1Discontinuous or discrete reinforcing fibers2.1.1 Natural/cellulose fibersFigure 2.1 illust
44、rates thestructure of wood. A piece of lumber may have defects, suchas knots or cracks, that adversely affect its strength. A pieceof clear wood (nearly defect-free at a macroscopic level)would have a tensile strength of approximately 70 MPa. Asingle wood fiber (natural/cellulose fiber), which const
45、itutesthe reinforcing unit of bulk wood, however, can have tensilestrength greater than 700 MPa (Coutts 1983).The major chemical components of wood are cellulose,hemicellulose, lignin, and a small fraction of extractives.Natural/cellulose fibers, in their natural arrangement in soft-woods and in har
46、dwoods, are bonded together by a layer ofamorphous cementing material. In the cellulose fiberproduction (pulping) process, this cementing material isbroken by either chemical or mechanical means to obtain theindividual cellulose fibers.Pulping processes are classified as chemical, semichemical,or me
47、chanical, based on how the original fibrous structure isbroken down. This classification refers to the nature of theprocess used to separate the fibers. In the mechanical pulpingprocess, frictional forces, often aided by steam pressure,separate the fibers. In the chemical process, the fibers aresepa
48、rated from one another primarily by dissolving andremoving the natural bonding agent. Semichemicalprocesses use a combination of chemical reactions andmechanical power to achieve the same objective (Kocurekand Stevens 1983; Suchsland and Woodson 1986). Chemicalpulp, also called kraft pulp, is common
49、ly used in the productionof book paper and writing paper, whereas mechanical pulp isused regularly for the manufacture of newsprint.Among commercial trees, softwoods are the source ofso-called long fibers. The length of unbroken cellulose fibersin important softwoods ranges between 2.5 to 7 mm, but thevast majority of fibers are between 3 to 5 mm in length. Evenwithin the same tree species, fiber lengths can vary considerably.The diameter of softwood cellulose fibers ranges between 15and 80 microns, but the majority of fibers ar
