1、548.6R-1Polymer concrete (PC) is used in the construction of structural elements.Applications include wall panels to carry wind and seismic loads; under-ground vaults that must resist lateral earth pressure; vault and utility boxcovers that are required to resist vehicle loads; machine tool componen
2、tssubject to a wide range of loadings; and railroad ties to resist static and dy-namic rail loads. Structural uses of PC components involve flexure, shear,bearing, and deflections. Creep, fatigue, and service temperature are im-portant aspects of these mechanisms. A need for defining and understandi
3、ngpolymer concretes structural properties and behavior therefore exists.Standards and codes governing design with polymer concrete have not yetbeen developed. There is a need for more research on structural behaviorbefore design criteria can be completed.Keywords: beams (supports); drainage; floors;
4、 insulating concretes; port-land cements; pipes (tubes); plastics, polymers, and resins; polymer con-crete; railroad ties; structural design; tools; wallsCONTENTSIntroduction, p. 548.6R-2Chapter 1Historic development, p. 548.6R-2Chapter 2Materials and properties, p. 548.6R-32.1Materials for structur
5、al polymer concrete2.2Polymer concrete types2.3Mechanical properties2.4Chemical and physical characteristics2.5Standards and guides applicable to polymer concrete2.6Safety2.7Regulatory matters2.8Materials research2.9Suggested additional researchACI 548.6R-96 became effective January 1, 1996.Copyrigh
6、t 1996, 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 reproductionor for use i
7、n any knowledge or retrieval system or device, unless permission in writingis obtained from the copyright proprietors.ACI 548.6R-96Polymer ConcreteStructural ApplicationsState-of-the-Art ReportReported by ACI Committee 548D. Gerry WaltersChairmanPaul D. KraussSecretaryJohn J. Bartholomew Arthur H. G
8、erber Rockwell T. RookeyGary Billiard Albert O. Kaeding Emanuel J. ScarpinatoW. Barry Butler Mohammed S. Khan Ernest K. SchraderRobert R. Cain Louis A. Kuhlman Qizhong ShengPaul D. Carter Henry N. Marsh W. Glenn SmoakFrank Constantino Stella L. Marusin Joe SolomonGlenn W. DePuy Joseph A. McElroy Mic
9、hael J. SprinkelFloyd E. Dimmick Peter Mendis Cumaraswamy VipulanandanWilliam T. Dohner John R. Milliron Harold H. Weber, Jr.Larry J. Farrell Richard Montani Ron P. Webster*Jack J. Fontana* Larry C. Muszynski David P. Whitney*David W. Fowler* Michael J. OBrien Yoga V. YogendranSandor Popovics* Membe
10、rs of subcommittee who prepared report. Chairman of subcommittee who prepared report.ACI Committee Reports, Guides, Standard Practices, DesignHandbooks, and Commentaries are intended for guidance inplanning, designing, executing, and inspecting construction.This document is intended for the use of i
11、ndividuals who arecompetent to evaluate the significance and limitations of its con-tent and recommendations and who will accept responsibility forthe application of the material it contains. The American Con-crete Institute disclaims any and all responsibility for the appli-cation of the stated pri
12、nciples. The Institute shall not be liable forany loss or damage arising therefrom.Reference to this document shall not be made in contract docu-ments. If items found in this document are desired by the Archi-tect/Engineer to be a part of the contract documents, they shallbe restated in mandatory la
13、nguage for incorporation by the Ar-chitect/Engineer.548.6R-2 ACI COMMITTEE REPORTChapter 3Structural members, p. 548.6R-123.1Flexural members3.2Compression members3.3Reinforced polymer concrete3.4Unreinforced polymer concrete3.5Sandwich panelsChapter 4Applications in structures, p. 548.6R-134.1Archi
14、tectural panels and facades4.2Transportation4.3Electrical insulators4.4Utility structures4.5Hydraulic structures4.6Hazardous waste containment4.7Machine toolsChapter 5Glossary of terms, p. 548.6R-18Chapter 6References, p. 548.6R-206.1Recommended references6.2Reference organizations6.3Cited reference
15、sAppendix 1Example polymer concrete formulations,p. 548.6R-23Appendix 2Typical polymer concrete properties,548.6R-23INTRODUCTIONPolymer concrete (PC) is used for structural applicationswhere strength, stiffness, durability, and ease in moldingprovide an advantage over alternate materials. An additio
16、nalattraction is that many types of reinforcement can be usedwith PC. This report presents the state of the art in structuraluses of PC. The information herein is separated into six ma-jor sections. Chapter 1 outlines the historic development ofPC used in structures. Chapter 2 presents a general des
17、criptionof PC and some of its properties. Chapter 3 deals with the de-sign implications for structural elements fabricated from PC.Chapter 4 describes structures that have been completed us-ing PC. A glossary of technical terms relating to PC is pro-vided in Chapter 5, and Chapter 6 lists references
18、 that containadditional information and background for PC structures.CHAPTER 1HISTORIC DEVELOPMENTThe use of polymers in concrete was developed in theUnited States under three general classifications, polymer-impregnated concrete (PIC), polymer modified concrete(PMC), and polymer concrete (PC). Poly
19、mer-impregnatedconcrete is a hydrated portland cement concrete impregnatedwith a monomer and subsequently polymerized in situ.Large-scale research on PIC commenced in the United Statesin 1966. Polymer modified concrete is a premixed materialin which either a monomer or polymer is added to a freshcon
20、crete mixture in a liquid, powdery, or dispersed phase,and subsequently allowed to cure, and if needed, polymer-ize in place. PMC is covered by other documents preparedby ACI (ACI 548.3R) and others.1 PIC has not been used incommercial applications and is virtually nonexistent in theUnited States to
21、day. PC was first used commercially in the1950s in the United States in the production of syntheticmarble, followed by the manufacture of architectural fac-ing panels in the late 1950s. By the mid 1970s, PC was usedas a repair material for Portland cement concrete structures,mainly on highways and b
22、ridges. The U.S. Federal High-way Administration, the Bureau of Reclamation, and theDepartment of Energy all sponsored materials researchduring the 1970s and the 1980s that included PC. In theUnited States in the 1980s, chemical companies developedan increasing interest in specific materials and mat
23、erialproperties required to produce PC. As a result, many en-hancements in the polymers used in PC were developed,and resins tailor-made for PC production began to be of-fered. This development continues, and material improve-ments are often achieved by manufacturers.Information and technical papers
24、 concerning PC and itsapplications were published as the result of the First Inter-national Congress on Polymers in Concrete (ICPIC) held inEngland in 1975. Subsequent congresses were held in Aus-tin, Texas, U.S.A. (1978), Koriyama, Japan (1981), Darm-stadt, Germany (1984), Brighton, England (1987),
25、 andPeoples Republic of China (1990). The Seventh Interna-tional Congress on Polymers in Concrete was held in Rus-sia in September 1992. All published proceedings includepapers on several structural aspects of PC. Fatigue, impact,abrasion, and flammability are discussed. Uses of PC instructures in t
26、he United States, Russia, India, Japan, Po-land, Germany, England and South Africa are described.The American Concrete Institute (ACI) formed Commit-tee 548, Polymers in Concrete, in 1971. Committee 548 haspublished proceedings of symposia held with AmericanConcrete Institute conventions. The commit
27、tee has alsopublished Polymers in ConcreteState-of-the-Art Report(ACI 548R) and Guide for the Use of Polymers in Concrete(ACI 548.1R). Several test methods specific to PC were de-veloped and published by the Polymer Concrete Committeeof the Society of the Plastics Industry, Inc. (See Table 4).Today,
28、 a major part of PC application is in the form ofprecast elements. At first, the only precast elements werearchitectural building panels. Beginning in the 1970s, otherstructural products began to appear on the market, includ-ing floor drains, utility trenches, underground utility vaultsand covers, h
29、igh-voltage insulators, and highway medianbarrier shells. These products were followed by the intro-duction of manhole structures and machine tool bases. Re-search into the behavior of PC structures is continuing atthe University of Texas (Austin), Brookhaven NationalLaboratory, the University of Ho
30、uston, the Federal High-way Administration, and various state highway departments.It is anticipated that many new PC materials and innova-tive uses for these materials will be on the market by thePOLYMER CONCRETESTRUCTURAL APPLICATIONS 548.6R-3turn of the century. Research is being conducted on such
31、uses as ballistics panels, electric transmission poles, sand-wich panels, building blocks, utility trenches, utility covers,and insulation panels.2CHAPTER 2MATERIALS AND PROPERTIES2.1Materials for structural polymer concreteThe general term, polymer concrete, used in this report in-cludes polymer mo
32、rtars, polymer grouts, and polymer con-cretes. Polymer mortars and grouts include materials withaggregate sizes smaller than 1/4 in. (6 mm). Differences be-tween mortars and grouts depend on the intended use and af-fect the fabricators formulation of the material.2.1.1 PolymersThermosetting polymers
33、 are used as thebinding matrix for structural PC applications. Frequentlyused polymers include those made from such monomers asmethacrylates, epoxy, furan, styrene, trimethylopropane tri-methacrylate, unsaturated polyesters (UP), and vinyl ester.The monomers of these polymers, or a mixture of monome
34、rsand polymers in liquid form, are mixed with an aggregatesystem to produce the mixture. Polymerization promotersand initiators are also included in the mix proportioning tocross-link or complete the polymerization (hardening) of themonomers. There are several properties of the monomers orpolymers t
35、ypically used to define the characteristics of theuncured PC. Polymer concretes and mortars are usually clas-sified based on the properties of the uncured binder, thecured binder, and the cured PC or mortar. For most appli-cations, the properties of the cured binder will dominate ma-terial selection
36、.The viscosity of the individual or mixed components maybe specified to control the coating of the aggregates. Binderresins with low viscosity are more suitable for highly-filledmixtures. A gel time range may be specified to insure thatthere is adequate time to place the fresh PC and that the cur-in
37、g will be completed within the time allotted beforedemolding. Additional properties of the uncured binders,such as specific gravity, shelf life, component content, andflash point, are sometimes specified.3Mixing procedures vary with the polymers selected. Thecombination of monomers, polymers, initia
38、tors, promoters,and chemical additives constitutes the binder system. Somebinder systems may be formulated as two componentswhere one component contains the monomers, polymers,promoters, and additives and the second contains the curingagent or initiator. Another common way to prepare the bind-er sys
39、tem is to premix the promoters and additives with partof the monomers and polymers (usually one-half) and topremix the initiators with the remaining portion. For a spe-cific binder system, the ingredient manufacturer or a chem-ist should be consulted to select the most appropriate way tomix the requ
40、ired chemicals. Particular care must be taken toavoid mixing promoters directly with initiators because themixture can react explosively. Refer to Paragraph 2.6 forsafety requirements.2.1.2 AggregatesAggregates such as silica sand, gran-ite, river gravel, basalt, fly ash, calcium carbonate, and sili
41、caflour are generally acceptable for PC. Individual fly ashesshould be tested before use since some may adversely affectthe polymerization reaction. Most aggregates meeting theStandard Specification for Concrete Aggregates, ASTM C 33,will provide adequate performance in PC. In addition, aggre-gates
42、must be selected for chemical resistance if that is a fac-tor in the application.4 Aggregates are usually specified to bedry (less than 0.2 percent free moisture) and free from dirt,clay, asphalt, and organic materials. Rounded river gravel upto 3/4 in. (20 mm) has been used for some overlays and is
43、 alsosuitable for precasting larger sections. The larger smooth ag-gregate provides a more workable mixture, and less resin canbe used.Concern for the preservation of the environment and theconservation of natural resources has focused attention onthe need to recycle waste materials such as plastics
44、, glass,and incinerator ash to produce useful products for the publicand private sectors. Waste glass is a major portion of all mu-nicipal waste, accounting for about 10.5 percent or 13.5 mil-lion tons (12.2 million Mg) in 1975. This glass fraction ofmunicipal solid waste is an inert aggregate that
45、may be usedin PC composites. Examples of glass-polymer compositesinclude sanitary pipe, culvert pipe, septic tanks, cesspools,and building blocks or brick. Municipal park benches and tablesand other decorative products normally made of portland ce-ment concrete can also be made of glass polymer comp
46、osites.52.1.3 ReinforcementThere are many types of reinforce-ment available for PC: bars and rods made from steel or fi-berglass; fabrics made from steel wire, fiberglass, orpolymers; and fibers made from steel, glass, carbon, or poly-mers. Ductile materials such as steel with high tensilestrength a
47、nd stiffness are generally preferred to provide theductile behavior and high flexural strength for the compo-nent. Fiberglass cloth or mats are frequently used as rein-forcement due to the ease of its placement in molds and itsdurability, strength, and chemical resistance.5The addition of various ty
48、pes of fibers can result in in-creases in the splitting tensile strength and ductility of PC.Increases in splitting tensile strength of 9 percent for 1-in.-(25-mm)-long AR (alkali resistant) glass fibers (2 wt. per-cent) and from 10 to 50 percent for various steel fibers (2 to7 wt. percent) have bee
49、n reported.62.1.4 AdditivesAdditives, such as air release agents,wetting agents, flexibilizers, shrinkage reducers, UV inhibi-tors, fire-resisting agents, and bond enhancers are added toPC polymers to improve one or more properties. Each ofthese additives is designed and selected to match the partic-ular polymer being used. Air release and wetting agents areused in polymer systems to remove air encapsulated duringmixing and to decrease the polymer content when a low-polymer-ratio PC is required. Flexibilizers are added to re-duce the modulus of
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