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98 for each site. Provide an interim report including a de- scription of the detailed procedures, a statistically valid experiment design for field testing the procedures, and a design for a pilot test. Task 3 Pilot test the approved procedures and ex- periment design through field studies at one or two sites, and makes any needed modifications. Task 4 Following approval of the revised procedures and experiment design, validate the procedures through field tests. Task 5 Prepare the final report, including documen- tation that can provide the basis for a nationally accepted test for use by all states. Tasks 1 and 2 have been completed. Project 3-40 FY ,89 Single Point Urban Interchange Design and Operations Analysis Research Agency: Principal Invest.: Effective Date: (~21 months) Completion Date: Funds: $250,000 In developmental stage The Single Point Urban Interchange (SPUI) essentially combines two separate diamond ramp intersections into one large at-grade intersection which accommodates all interchanging vehicular movements and the through traffic. Signalization of the one major intersection sim- plifies coordination on the arterial. It has been reported that SPUIs can significantly increase traffic-carrying ca- pability compared with the conventional diamond inter- change. There are currently numerous uncertainties about the design and operation of SPUIs. These include: wrong- way movement potential; traffic signal, signing, and de- lineation requirements; sight distance; cost-effectiveness; increased capability to accommodate heavy traffic move- ments; safety problems; and driver behavior. The objectives of the research are (1) to document current practice in design and traffic operations at existing SPUIs and (2) to develop and document guidelines for the design, operation, analysis, and cost effectiveness of SPUIs. Accomplishment of the objectives will require, as a minimum, the following tasks: Task 1- Determine the state of the art and current practice through a review of the literature and contacts with highway agenices planning, designing, constructing, operating, and maintaining SPUIs. Task 2 Prepare an interim report which documents the results of Task 1, describes and illustrates key factors in the design of SPUIs, and lists key strengths and weak- nesses experienced to date. The report shall also include recommended refinements of the research plan for the remainder of the project. Task 3 Develop guidelines to assess the cost effec- tiveness of SPUIs in comparison with alternative design solutions on a life-cycle basis (right-of-way, pavement, structures, drainage, and function), including first costs, continuing agency costs, user costs, and environmental costs. Task 4 Develop guidelines for geometric design for use with the AASHTO "Green Book." Guidelines should consider, but not be limited to, the following: turning radii, design speed, free flow movements, channelization design including provision for U-Turns, pedestrian and bicycle accommodations, horizontal and vertical sight dis- tance, capacity, frontage and service roads, and access control. Task 5 Develop guidelines to analyze the functional performance of SPUI traffic operations throughout its design life (these may be based on existing computer programs). Develop criteria for the optimum placement and operation of traffic control devices. Define safety con- siderations, including pedestrian and bicycle traffic, and develop recommendations for dealing with the impact of these factors. Task 6; Prepare a final report, documenting the re- search and presenting the findings, with emphasis on the user guidelines for those highway agencies contemplating selection, design, construction, operations, and mainte- nance of SPUIs. Tasks 1 and 2 have been completed. AREA 4: GENERAL MATERIALS Project 4-1 FY '63 and FY '64 Development of Appropriate Methods for Evaluating the Effectiveness of Stabilizing Agents Research Agency: Principal Invest.: Effective Date: Completion Date: Funds: University of Illinois Dr. E. J. Barenberg June 1, 1963 October 31, 1966 $1 14,991 This study was directed toward the further improve- ment of existing methods or the development of new methods of tests which will lead to a way of measuring the effectiveness of various stabilizing agents. The meth- oafs are expected to provide definitive data to predict performance under in-service conditions and provide cri- teria for the design and construction of pavement com- ponents involving stabilized materials. This research was conducted principally by means of laboratory experiments to investigate the effectiveness of viscous and nonviscous materials as stabilizing agents. Type I Portland cement and a penetration-grade asphalt
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99 were chosen for the study because of their popularity as reflected in current usage, and limited tests of model pavements stabilized with both these materials were con- ducted in the research agency's test track for the purpose of correlating the results obtained in the laboratory with the behavior of the model pavements. The project report was not published in the regular NCHRP report series; however, microfiche of the report may be purchased (see final page of this section for or- dering information). Project 4-2 FY ,63 and FY '64 A Study of Degrading Aggregates in Bases and Subbases with Production of Exces- sive Amounts of and/or Harmful Types of Fines Research Agency: Purdue University Principal Invest.: Dr. R. B. Johnson Dr. N. B. Aughenbaugh Dr. N. M. Smith Dr. T. R. West Elective Date: February 15, 1963 Completion Date: November 30, 1966 Funds: $63,990 This study was directed toward the development of tests or procedures for predicting the amount and effects of aggregate degradation and the development of tech- niques for upgrading such aggregates for economic use in highway pavement structures. The research has been completed, and the project report has been published as: NCHRP Report 98, "Tests for Evaluating Degradation of Base Course Aggregates." Project 4-3~1) FY '63 and FY '66 Development of Methods to Identify Aggre- gate Particles Which Undergo Destructive Volume Changes When Frozen in Con- crete Research Agency: Principal Invest.: Elective Date: Completion Date: Funds: Virginia Polytechnic Institute Dr. R. D. Walker Mar. 1, 1963 July 1, 1965 Sept. 30, 1964 Mar. 31, 1967 $20,000 $23,337 Research conducted under this study related to the development of a rapid method of testis) to distinguish deleterious particles in aggregates and to predict their behavior under various degrees of exposure in concrete subjected to freezing and thawing. The work was similar to that conducted under Project 4-3~2) at Pennsylvania State University (the same objectives apply) but different in approach. Certain aggregates investigated were com- mon to both studies. The initial research phase has been completed, and the project report for this phase has been published as: NCHRP Report 12, "Identification of Aggregates Caus- ing Poor Concrete Performance When Frozen." The final research phase has been completed, and the project report has been published as: NCHRP Report 65, "One-Cycle Slow-Freeze Test for Evaluating Aggregate Performance in Frozen Concrete." Project 4-3~2) FY '63 and FY '66 Development of Methods to Iclentify Aggre- gate Particles Which Undergo Destructive Volume Changes When Frozen in Con- crete Research Agency: Principal Invest.: Elective Date: Completion Date: Funds: The Pennsylvania State University Dr. T. D. Larson Mar. 25, 1963 July 1, 1965 Jan. 31, 1965 Aug. 31, 1967 $56,457 $49,756 This project involved the development of a rapid testis) to distinguish deleterious particles in aggregates and thereby predict their behavior under various degrees of exposure in concrete subjected to freezing and thawing. The study was similar to that conducted under Project 4-3~1) at Virginia Polytechnic Institute (the same objec- tives apply) but different in approach. A number of ag- gregates investigated were common to both studies. The initial research phase has been completed, and the project reports for this phase have been published as: HRB Special Report 80, "A Critical Review of Literature Treat- ing Methods of Identifying Aggregates Subject to De- structive Volume Change When Frozen in Concrete and a Proposed Program of Research," and NCHRP Report 15, "Identification of Concrete Aggregates Exhibiting Frost Susceptibility." The final research phase has been completed, and the project report has been published as: NCHRP Report 66, "Identification of Frost-Susceptible Particles in Concrete Aggregates." Project 4-4 FY '63 Synthetic Aggregates for Highway Uses Research Agency: Principal Invest.: Effective Date: Completion Date: Funds: Battelle Memorial Institute M. J. Snyder F. F. Fondriest March 1, 1963 Aprill5,1964 $14,790 In an effort to determine potential sources of aggre- gates, this study was authorized to explore the feasibility of utilizing artificial aggregates in highway construction. Research has been completed, and the project report has been published as: NCHRP Report 8, "Synthetic Aggregates for Highway Construction."
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100 Project 4-5 FY 963 A Study of the Mechanism Whereby the Strength of Bases and Subbases is Af- fected by Frost and Moisture Research Agency: Principal Invest.: Effective Date: Completion Date: Funds: Michigan Technological University Dr. W. M. Haas February 15, 1963 August 31, 1965 $64,105 This project involved an extension of present knowledge and understanding of the phenomena of the action of frost and moisture in bases and subbases. Initially, lab- oratory models were developed which incorporated sig- nificant variables as an aid in analyzing the mechanism of frost action and its relation to strength. Hypotheses evolving from the laboratory were checked in the field. The project report was not published in the regular NCHRP report series; however, microfiche of the report may be purchased (see final page of this section for or- dering information). Project 4-6 FY '65 Projective Coatings for Highway Structural Steel orally Grades 60 and 75) to support realistic design cri- teria. This was approached through the design and execution of a statistically valid experiment. Phase I experimental work consisted of repeated-load tests on rectangular and T-shaped concrete beams rein- forced with a single longitudinal bar. These specimens contained bars ranging in size from No. 5 to No. 11 and having nominal yield stresses from 40 to 75 ksi. Major emphasis in the Phase I study was on stress range, min- imum stress, bar diameter, type of specimen, and grade of bar. Phase II had the objectives of (1) determining the erect of surface geometry (deformation pattern and details) and (2) incorporating the results of Phases I and II into a single final report. A total of 353 fatigue tests was con- ducted in the two phases of work. On the basis of the observed behavior, a fatigue design provision was developed for deformed reinforcing bars suggesting a limitation on the service load stress range. Research has been completed, and the project report published as: NCHRP Report 164, "Fatigue Strength of High-Yield Reinforcing Bars." Project 4 8 FY '68 Research Needs Relating to Performance of Aggregates in Highway Construction Research Agency: Steel Structures Painting Council PResearch Agency: Virginia Polytechnic Institute r~nc~pa~ Invest.: John D. Keane Principal Invest.: Dr. R. D. Walker Elective Date: March 1, 1965 '. Completion Date: November 30, 1966 Effective Date: January 1, 1968 Funds $25 000 Completion Date: April 30, 1969 ' Funds: $55,254 This research involved a state-of-the-art review, field exposure testing on which definitive rankings may be based, and the development of plans for research to ac- quire needed information where adequate coatings are not available. Research has been completed, and the final report has been published as: NCHRP Report 74, "Protective Coat- ings for Highway Structural Steel." In addition, the fol- lowing documents have been published in extremely limited quantities: NCHRP Report 74A, "Protective Coatings for Highway Structural Steel Literature Sur- vey," and NCHRP Report 74B, "Protective Coatings for Highway Structural Steel Current Highway Practices." Project 4-7 FY '68 and FY '69 Fatigue Strength of High-Yield Reinforcing Bars Research Agency: Portland Cement Association Principal Invest.: Dr. John M. Hanson Dr. Thorsteinn Helgason Effective Date: Oct. 1, 1967 Feb. 1, 1971 Completion Date: Feb. 28, 1970 Aug. 31, 1973 Funds: $100 000 $50 000 ' The objectives of this project were: 1. To evaluate current and proposed procedures and criteria for the setting of density standards. The principal objective of this study was to obtain fatigue strength test data on ASTM A432 steel bars (gen The objective of this research was to formulate a com- prehensive series of statements of research problems and recommended studies (including estimates of time, cost, and priority) which have as their objective the develop- ment of procedures by the use of which a highway ma- terials engineer may evaluate quantitatively the relevant properties of aggregates to be selected for a given class of use in a given environment of service for a given level of performance. Research has been completed, and the project report has been published as: NCHRP Report 100, "Research Needs Relating to Performance of Aggregates in Highway Construction." Project 4-8~2) FY '71 Density Standards for Field Compaction of Granular Bases and Subbases Research Agency: Principal Invest.: Effective Date: Completion Date: Funds: Clemson University J. P. Rostron Aprill,1971 June 30, 1973 $95,248
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101 2. To illustrate examples of inadequate standards and the consequences of such inadequacy. 3. To develop new or revised procedures and criteria for more appropriate density standards. 4. To illustrate that the new or revised procedures and criteria would yield adequate density standards. 5. To draft, in a form suitable for adoption or adap- tation by highway departments, proposed new or revised procedures and criteria for the setting of density standards to control compaction during the construction of granular bases and subbases. Research has been completed, and the project report has been published as: NCHRP Report 172, "Density Standards for Field Compaction of Granular Bases and Subbases." Project 4-8(3) FY '72 and FY '76 Predicting Moisture-Induced Damage to As- phaItic Concrete Research Agency: Principal Invest.: Effective Date: Completion Date: Funds: University of Idaho Dr. Robert P. Lottman Sept. 1, 1971 Aug. 1, 1975 Mar. 31, 1974 Jan. 31, 1982 $190,177 $70,860 The objective of this project was to meet the need for a laboratory testing system that will quantitatively predict the ability of asphaltic concrete to resist the detrimental effects of moisture under field conditions. Research on Phase I included sampling and laboratory testing of mixtures composed of materials from many pavements in service, some of which were experiencing moisture damage and some not. Effort was made to re- produce in the laboratory the observed response to mois- ture in the field. The study produced a tentatively proposed system of tests for determining the moisture susceptibility of asphaltic concrete mixtures and a detailed work plan for a field evaluation of the system. The primary research program was conducted by the University of Idaho, with assistance by Battelle-Northwest and the Uni- versity of Washington. The final report for Phase I has been published as: NCHRP Report 192, "Predicting Moisture-Induced Damage to Asphaltic Concrete." Research on Phase II has been completed. The pre- dicted and observed performance over a 5-year period of 8 asphaltic concrete pavements in various climatic regions provided substantial verification of the tentative system of tests developed under Phase I. The American Asso- ciation of State Highway and Transportation Officials (AASHTO) has adopted the test procedure as T283-85, "Resistance of Compacted Bituminous Mixtures to Mois- ture-Induced Damage." The project report for Phase II Has been published as: NCHRP Report 246, "Predicting Moisture-Induced Damage to Asphaltic Concrete Field Evaluation." Project: 4-8(4) FY'84 Predicting Moisture-Induced Damage to Asphaltic Concrete-10 Year Field Eval- uation Research Agency: Principal Invest.: Elective Date: Completion Date: Funds: University of Idaho Dr. Robert P. Lottman June 1, 1985 January 31, 1987 $24,402 Under Project 4-8~3), a laboratory test was developed for predicting moisture-induced damage and the test was used to predict the performance of asphaltic concrete pavements on eight construction jobs. After 5 years of service, ranking of the pavement sections in terms of visual evidence of stripping and strength ratios of cores removed from the pavements was very similar to the predicted ranking produced by the laboratory tests. The objective of this project was to further verify the ability of the previously developed test methods to predict moisture-induced damage in terms of distress in the as- phaltic concrete layer and performance of the pavement surface courses by the collection and analysis of additional data from the eight pavement test sections after 10 years of service. Research has been completed and the preliminary draft final report has been reviewed and approved by the project panel. The agency report has been distributed to the Pro- gram sponsors and other interested persons. It will not be published in the regular NCHRP report series, but loan copies are available upon written request to the NCHRP or a microfiche may be purchased (see final page of this section for ordering information). Project 4-9 FY '69 Evaluation of Preformed Elastomeric Pave- ment Plaint Seating Systems and Practices Research Agency: Principal Invest.: Elective Date: Completion Date: Funds: Utah Department of Transporta tion Dale E. Peterson Oct. 1, 1968 Oct. 1, 1972 June 30, 1971 Dec. 31, 1979 $93,494 $144,837 The objective of this project was the development of guide specifications for use of preformed elastomeric joint seals in Portland cement concrete pavements. The re- search involved (1) a review and analysis of existing in- formation, (2) an extensive laboratory testing program, and (3) a field evaluation phase. Research has been completed with successful devel- opment and field verification of guide specifications. A major finding of the study is that the ability of elastomeric sealing systems to prevent intrusion of moisture and for- eign material is more dependent on the adhesion between the seal and the pavement joint surface than on the pres
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102 sure exerted by the compression of the seal. Consequently, selection of and specifications for the lubricant-adhesive used during installation is a very important factor in long- term performance of the system. The essential findings of the study have been published as NCHRP Research Results Digest 123. The agency report has been distributed to program sponsors. It will not be published in the regular series. Project 4-10 FY '70 Promising Replacements for Conventional Aggregates for Highway Use Research Agency: Principal Invest.: Elective Date: Completion Date: Funds: University of Illinois Dr. C. R. Marek October 15, 1969 March 31, 1971 $50,000 The purpose of this project was to study the utilization of modern technology as it might apply to the develop- ment of substitute materials and/or new procedures for upgrading existing unsuitable materials for use as aggre- gates in Portland cement concrete, bituminous mixes, and base courses. This research has been completed, and the project re- port has been published as: NCHRP Report 135, "Prom- ising Replacements for Conventional Aggregates for Highway Use." Project 4-10A FY '70 Waste Materials as Potential Replacements for Highway Aggregates Research Agency: Valley Forge Laboratories Principal Invest.: Richard H. Miller Elective Date: September 1, 1972 Completion Date: November 30, 1973 Funds: $53,663 NCHRP Project 4-10, "Promising Replacements for Conventional Aggregates for Highway Use," identified the potential for using waste materials as aggregate in highway construction. The objectives for Project 4-1 OA, as developed from the prior effort, were to: 1. Provide an inventory of the types, sources, and quan- tities of waste materials potentially suitable for the pro- duction of synthetic aggregates or for otherwise replacing conventional aggregates in highway construction. 2. Provide an assessment of the prospects for practical use of specific waste materials for production of synthetic aggregates or otherwise replacing the need for conven- tional aggregates in highway construction, particularly where aggregate supplies are scarce. Based on technical, economic, and environmental eval- uations, 30 waste materials were found to have some potential for use as highway aggregates. The basic tech- nology was judged to exist for converting any one of the materials into aggregate, but in most instances much ex- perimentation remains to be done. Research has been completed, and the project report has been published as NCHRP Report 166, "Waste Ma- terials as Potential Replacements for Highway Aggre- gates." Project 4-11 FY '75 Buried Plastic Pipe for Drainage of Transpor- tation Facilities Research Agency: Principal Invest.: Elective Date: Completion Date: Funds: Simpson Gumpertz & Heger Frank J. Heger R. E. Chambers September 16, 1974 January 26, 1979 $200,000 At the time the research problem was conceived, a number of plastic pipe products were available to the transportation industry that appeared to have good po- tential for economical use as underdrains, storm sewers, culverts, and other drainage structures. However, because of the lack of experience with these products in trans- portation facilities, their use was limited in these appli- cations. Understandably, there was a reluctance to use them in place of, or as alternates to, more conventional pipe products whose in-service behavior had been estab- lished by many years of experience. Accordingly, a need existed for an evaluation of the theoretical considerations and field performance of buried plastic pipe to determine under what conditions they could be used in transpor- tation facilities. Several piping systems were found to be appropriate for transportation drainage applications. Perforated cor- rugated polyethylene (PE) tubing, perforated polyvinyl chloride (PVC), and acrylonitrile-butadiene-styrene (ABS) pipe were selected for underdrains. PVC pipe and ABS composite pipe were selected for storm drains and small culverts. Advantages and possible limitations, are presented. In addition, guidelines for selecting, designing, and installing plastic pipe were developed including sam- ple design problems, recommended specifications for two types of plastic pipe products (corrugated polyethylene tubing and polyvinyl chloride piping), and a recom- mended standard for field installation practices. Research has been completed, and the project report has been published as: NCHRP Report 225, "Plastic Pipe for Subsurface Drainage of Transportation Facilities."
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103 Project 4-12 FY '77 Upgrading of Poor or Marginal Aggregates For PCC and Bituminous Pavements Research Agency: The Pennsylvania State University Principal Invest.: Dr. Philip D. Cady Elective Date: December 1, 1976 Completion Date: May 31, 1979 Funds: $ 149,941 The over-all objective of this study was to advance methods of upgrading poor or marginal-quality coarse aggregates to acceptable durability and structural levels for use in high-type bituminous and PCC pavement mix- Research Agency lures. The procedures for upgrading aggregates in this Principal Invest study were limited to the use of different types of coatings, Effective Date: chemical treatments, or impregnation with plastics or Completion Date: other materials. Funds: The beneficiation addressed recognized problems such as freeze-thaw damage, stripping, degradation, inadequate soundness, alkali-aggregate reactions, destructive volume changes, and objectionable coatings. This study did not address itself to pavement surface characteristics, such as skid properties, texture and rough- ness, or mixtures applied as seal coats or thin surface treatments. Research has been completed, and the final report has been published as: NCHRP Report 207, "Upgrading of Low-Quality Aggregates for PCC and Bituminous Pave- ments." Project 4-13 FY '77 Temporary Pavement Marking Systems Research Agency: Principal Invest.: Elective Date: Completion Date: Funds: Southwest Research Institute John M. Dale November 1, 1976 February 28, 1978 $49,500 The specific objectives of this research were: (1) To examine one or more concepts, existing or new, that offer promise for development into workable temporary pave- ment marking systems. The desired characteristics of these systems include delineation quality, ease of instal- lation and removal, absence of adverse environmental effects, ease of implementation, and cost-effectiveness. (2) To analyze the feasibility of the concept or concepts in comparison with existing practice with reference to, but not limited to: (a) manpower, equipment, and material costs (application and removal), (b) effect on traffic during application and removal, (c) traffic control effectiveness, (d) system durability, (e) material and process availability, and (f) hazards to workmen during application and re- moval The concept of this research was to develop and eval- uate additives to be used with existing traffic paints. Re- search began with lab tests of candidate additives of four types: those with water of hydration, blowing agents, fuels, and oxidizers. No practicable material was found to meet the requirements of the project. A final report has been submitted and is available on a loan basis upon written request to the NCHRP. Further research of temporary marking materials, pur- suing other approaches, has been resumed under Project 4-13A. Project 4-13A FY '77 Temporary Pavement Marking Paint Systems Georgia Institute of Technology Dr. Charles J. Ray April 1, 1978 September 30, 1979 $69,971 The specific objectives of this research were: (1) to examine new paint formulations, primer materials, and related combinations that offer promise for development into workable temporary pavement marking systems; and (2) to analyze the feasibility of the concept or concepts in comparison with existing practice. A wide range of materials and removal processes was investigated. Coatings based on vinyl chloride copoly- mers, chlorinated rubber, and acrylic resins were tested. Removal techniques included photolysis, biodegradation, thermal degradation, and chemical degradation. The re- moval tests were inconclusive. Research has been completed. The agency's final report will not be published but is available on a loan basis upon written request to the NCHRP. Project 4-14 FY '78 Coating Systems for Painting 01d and New Structural Steel Research Agency: Principal Invest.: Effective Date: Completion Date: Funds: Georgia Tech Research Corpora- tion Dr. D. J. O'Neil F. A. Rideout Dr. Charles Ray January 1, 1978 December 31, 1981 $199,302 The objective of this research was the preparation of tentative guidelines for the use of existing and recently developed nonproprietary coating systems for the painting of structural steel with emphasis on such considerations as (a) health and environment, (b) exposure conditions, (c) application requirements, and (d) economics. Research has been completed with partial accomplish- ment of objectives. Tentative guidelines for selection of new coating systems have been developed but additional field testing is needed for verification.
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104 Copies of the agency report were distributed to program sponsors and will not be published in the regular NCHRP report series. Loan copies are available or microfiche of the report may be purchased (see final page of this section for ordering information). Project 4-15 FY '82 Corrosion Protection of Prestressing Systems in Concrete Bridges Research Agency: Principal Invest.: Elective Date: Completion Date: Funds: Wiss, Janney, Elstner Associates, Inc. William F. Perenchio July 1, 1982 November 30, 1985 $250,000 The objectives of this research are (1) to prepare summary report of available technology for the corrosion protection of prestressing steel, (2) to develop and dem- onstrate a coating or duct system of corrosion protection for bonded post-tensioning steel, and (3) to identify a feasible system for corrosion protection of pretensioning strands. Attainment of the project objectives necessitates the following tasks. Task 1. Identify those techniques that have been used specifically to protect pretensioning and post-tensioning steel, ducts, and anchorages from corrosion; evaluate their effectiveness based on available research and field expe- rience; and forecast their long-term (50 to 100 years) performance. Write a report summarizing the results and identifying promising corrosion protection systems. Spe- cifically recommend a system for the corrosion protection of post-tensioning wires, strands, and bars to be further evaluated under Task 2. Task 2. Perform mechanical and other tests to dem- onstrate the practical use of the selected post-tensioning corrosion protecting system in situations encountered in the field, particularly in segmental bridge applications. Such testing should include, but not be limited to: (1) friction, (2) bond, (3) mechanical abrasion and damage, (4) continuity of protection at anchors, (5) compatibility with the Portland cement concrete and grout environ- ment, and (6) effectiveness of the system in protecting the prestressing steel from corrosion. Based on the test results, write a recommended practice for the design and con- struction of a corrosion protection system for post- tensioning. Task 3. Determine performance requirements for non- metallic coating of 7-wire strands used for pretensioning, including but not limited to the following: (1) chemical and physical compatibility with base metal, (2) effective- ness in controlling corrosion, (3) bond with steel and with concrete, (4) resistance to injury during handling, (5) problems associated with coiling and flexure of the strand, (6) effects of anchorage devices, (7) strain compatibility, and (8) quality control (especially the control of"holi- days"~. Identify and evaluate candidate coating materials, and determine the feasibility of applying the coatings through direct contact with strand and coating manufac- turers and coating applicators. Based on the research done, report on the technical and economic feasibility of a nonmetallic coating system for strands. Task 4. Prepare final report documenting all research. The Task 1 agency interim report has been submitted, reviewed, and distributed to all NCHRP sponsors. It is available to others on a loan basis or for purchase of Xerox copies (see final page of this section for ordering information). Based on recommendations from the Task 1 interim report, an updated research plan was submitted and ap- proved for accomplishing the remaining tasks. Under a Task 2, tests for mechanical behavior and corrosion re- sistance in posttensioning applications include various combinations of plastic, galvanized metal, epoxy coated metal, and bare metal ducts; uncoated and epoxy-coated anchorage hardware and 7-wire strands; and corrosion inhibiting admixtures for grouts. The testing procedures for Task 2 have not changed dramatically from those originally proposed; however, those under Task 3 have. Task 3 was originally conceived as a feasibility study for epoxy coating 7-wire strand most likely to be used in pretensioning applications. Since the original conception of the project, an epoxy-coated 7-wire strand is now com- mercially available and is being used in some limited applications. Consequently, work under the updated re- search plan for Task 3 no longer focuses on feasibility, but on actual tests for mechanical behavior and corrosion resistance. The research project is complete. After experiencing extreme delays in analyzing and documenting the re- search, the agency has submitted a revised final report which is now in the publication process. Project 4-16 FY '84 Cost and Service Life of Pavement Markings Research Agency: Principal Invest.: Elective Date: Completion Date: Funds: Pennsylvania State University Dr. John J. Henry October 1, 1984 September 30, 1988 $340,327 A wide variety of materials is available for the marking of streets and highways. Traffic paints have been the main- stay of marking materials for the past 60 years, but the recognition that such paints have severely limited ser- viceability in locations of high traffic volumes and/or extreme climate has led in the past 20 years to the in- creasing use of "durable" marking materials. Traffic paints are either latex-based or solvent-based comprised of alkyd, chlorinated rubber, or epoxy resins.
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105 In severe service conditions such materials may provide 6 months or less useful life. Durable marking materials generally are solventless systems and can be epoxy, polyester, or either hydrocarbon or alkyd thermoplastic materials. Their service life when properly applied can approach 3 or more years. Traffic paints traditionally have been applied by state and municipal forces, whereas du- rable marking materials are generally applied by private firms under contract. At present, applied traffic paints can cost from $0.025 to $0.06 per lineal foot (4-inch line), while durable mark- ings can cost from $0.055 to $1.25 per lineal foot. Cost disparities also exist for special markings, such as cross- walks, turn arrows, and other in-lane markings. A higher initial cost may be justified if the elective service life of the durable material exceeds that of traffic paint in the same location. Higher costs may also be justified by the more intangible benefits of continuous, year-round delin- eation and reduced exposure of striping personnel and the public to hazardous striping operations. Such benefits are particularly important for special markings. In some cases, environmental restrictions may dictate the selection of marking materials. The judgment of whether the cost of a material is reasonable for a particular set of circumstances (climate, traffic volume, condition of previous markings, pavement type, highway geometry, etc.) should be made on the basis of its probable service life. However, factual data on which to base such judgments are scarce. Some general infor- mation is available from field tests and operational use of various types of pavement marking materials, but there has been little to no specific treatment of the problem of how to select a cost-effective marking material for a par- ticular set of circumstances. In addition, the influence of width (4, 6, and 8 inches) on the effective service life of traffic lines has not been established. This lack of com- prehensive data is disturbing in light of stringent budgets. The objective of this research is to determine the typical "on-road" service life and cost of various types of pave- ment marking materials and to quantify how major ex- ternal factors affect service life. In addition, the effect of traffic line width on service life will be determined. Max- imum use will be made of existing information from field tests and operational installations, and a limited amount of new field testing will be conducted. Guidelines will be developed for the use of commercially available pavement marking materials, including selection criteria affecting the optimum balance between cost and service life. The materials to be evaluated include: paint, epoxy, epoxy paint, alkyd and hydrocarbon thermoplastics, polyester paints, epoxy thermoplastic, and preformed materials. A list of the research tasks follows: 1. Compile comparative data on the performance and total cost installed of commercially available traffic paint and durable marking materials through a critical review of published results, a survey of selected state and large municipal highway agencies, and personal follow-up where appropriate. . 2. Critically analyze the data to develop comparative estimates of the service life of traffic paint and durable marking materials within the ranges of external factors, such as climate, traffic volume, traffic mix, highway ge- ometry, and type and condition of pavement and previous markings. Develop estimated installed costs per foot for each material type. 3. Prepare an interim report with a detailed test plan for Task 4. Prepare a priority listing of all tests needed to provide information covering the full range of materials and conditions. From this list, select specific materials and conditions for field testing within the limited funds of this project. 4. Conduct tests according to the approved test plan. 5. Prepare guidelines for selection of the appropriate pavement marking materials identifying the erects of ma- jor external factors. The intent of these guidelines is to allow users to determine life-cycle costs for various mark . ing maters s. The final report is being prepared. Project 4-17 FY '85 Environmental Monitoring and Evaluation of Calcium Magnesium Acetate (CMA) University of Washington Dr. Richard R. Homer January 7, 1985 October 31, 1987 $199,943 Because of the environmental deficiencies of conven- tional deicers, sodium and calcium chloride, the Federal Highway Administration (FHWA) initiated research to find a suitable alternative. As a result, calcium magnesium acetate (CMA) had been identified as a possible alternative deicing chemical. To determine potentially undesirable environmental impacts, a chemically pure CMA had been evaluated. Laboratory investigations by Caltrans included impacts to terrestrial vegetation, impacts to aquatic ecosystems, leaching characteristics in the soil, potential atmospheric effects, occupational exposure, impacts to ground and surface water supplies, and public health implications. Results of this preliminary laboratory research indicated that pure CMA has no significant detrimental effects to the environment. However, the manufacture of pure CMA was an expensive process. Efforts to develop a more economical method for production of CMA were under- way. Research conducted by SRI International had identified a process to manufacture CMA in large quantities by fermentation of corn grain sugars with bacterium, Clos- tridium thermoaceticum. Based on this preferred process, an FHWA research contract to develop a mutant bacterial Research Agency: Principal Invest.: Elective Date: Completion Date: Funds:
Representative terms from entire chapter: