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A P P E N D I X A Annotated Bibliography Alberta Ministry of Transportation (Alberta MOT). Guidelines for higher than in the preceding 2 years and increased demand for capacity- Assessing Pavement Preservation Treatments and Strategies. Alberta improvement projects, it is more important than ever to use in-place MOT, Edmonton, Alberta, Canada, 2006. materials when rehabilitating pavement structural sections. Cold in- No abstract available. place recycling (CIR) and full-depth reclamation (FDR) are two pavement rehabilitation strategies that the Nevada Department of Transportation American Meteorological Society (AMS). Climate. Glossary of Meteo- (NDOT) has used for more than 20 years. These strategies have allowed rology. AMS, Boston, Mass., 2008. NDOT to save more than $600 million over the past 20 years compared No abstract available. with complete-reconstruction costs. In addition, traffic interruptions Applied Pavement Technology, Inc. (APTech). Asphalt Pavement Recy- are minimized during construction, and natural resources are pre- cling Technologies. Participant Workbook. NHI Course No. 131050. served. According to the Highway Performance Monitoring System Publication FHWA-NHI-02-061. National Highway Institute, FHWA, data, NDOT has the highest percentage of its combined National High- U.S. Department of Transportation, 2002. way System Interstate and other roadways rated in the "good" category. No abstract available. The reason for this achievement is that NDOT uses a proactive pave- ment management system (PMS) to prioritize its pavement preserva- Austroads Inc. Fibre-Reinforced Seals. Austroads, Inc., Sydney, tion projects. A considerable amount of CIR and FDR rehabilitation Australia, 2005. work is performed in conjunction with the proactive PMS. Because No abstract available. these strategies are more cost-effective than overlay, mill and overlay, Beatty, T. L., D. C. Jackson, D. A. Dawood, R. A. Ford, and J. S. or reconstruction, NDOT can rehabilitate more roads with less Moulthrop. Pavement Preservation Technology in France, South Africa, money. This report describes how to select, design, and construct suc- and Australia. Report FHWA-PL-03-001. FHWA, U.S. Department cessful CIR and FDR projects. The performances of the strategies are of Transportation, 2002. evaluated, and life-cycle cost analysis is developed to demonstrate the An increasing number of highway agencies have found that applying cost-benefit of CIR and FDR versus conventional rehabilitation relatively low-cost surface preservation treatments can extend the ser- strategies. vice life of a pavement. The Federal Highway Administration, American California Department of Transportation (Caltrans). Maintenance Association of State Highway and Transportation Officials, and National Technical Advisory Guide (MTAG): Volume I--Flexible Pavement Cooperative Highway Research Program sponsored a scanning study of Preservation, 2nd ed. Caltrans, Sacramento, Calif., 2008. www.dot France, South Africa, and Australia to investigate innovative programs .ca.gov/hq/maint/MTA_GuideVolume1Flexible.html. for pavement preservation. The U.S. delegation observed that the coun- This publication was prepared by HQ Maintenance to assist in making tries visited are committed to designing and building long-lasting better and more informed decisions on maintenance practices. It is structural pavement sections on their national roadway networks. The designed for several levels of use, ranging from general instruction to countries focus on road maintenance, using low-cost seals and thin over- specific work practice descriptions. It should be of use to district main- lays on surfaces to protect their investment in underlying layers, rather tenance managers, maintenance supervisors, superintendents, and than on more costly rehabilitation. The scanning team's recommenda- field personnel. Construction personnel and designers may also find tions for U.S. application include developing demonstration projects use for the information. This publication consists of several parts. The using deep-subbase and deep-base roadway designs, testing innovative first chapter is a review of pavement preservation and maintenance procedures to improve chip seal performance, conducting a best-practices principles, as well as a detailed technical discussion on the materials seminar on long-term maintenance contacts, and evaluating pavement used in maintenance treatments. This is followed by a chapter describing condition survey vehicles. a simplified treatment-selection process. The remaining Chapters 38 Bemanian, S., P. Polish, and G. Maurer. State-of-the-Practice on CIR describe the various maintenance treatments currently in use by Cal- and FDR Projects by Nevada DOT. Presented at 85th Annual Meet- trans and provide information on how to design and construct them. ing of the Transportation Research Board, Washington, D.C., 2006. Chapters 38 can be used as stand-alone documents for the respec- One of the biggest challenges that public agencies face is how to opti- tive treatments. Other chapters on new treatments may be added at a mize available funding. With the price of bituminous materials 70% later time. 93

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94 Chen, D. H., D. F. Lin, and H. L. Luo. Effectiveness of Preventive pavements. Diamond grinding consists of removing surface irregulari- Maintenance Treatments Using Fourteen SPS-3 Sites in Texas. ties from concrete pavements that are often caused by faulting, curling, Journal of Performance of Constructed Facilities. Vol. 17, No. 3, 2003, and warping of the slabs. The main benefits of properly using this tech- pp. 136143. nique include smoother ride, reduced road noise, and improved fric- Fourteen Texas SPS-3 test sites were studied to determine effectiveness tion. Diamond grinding can be used as a stand-alone rehabilitation of preventative maintenance treatments (PMTs). These sections were technique. However, FHWA recommends its use as part of a compre- built on four highway classifications (IH, US, SH, and FM) in different hensive concrete pavement rehabilitation (CPR) program. Information climates and with different levels of traffic and subgrade support. Almost regarding cost and performance is also included in this document. This all 14 SPS-3 sites were given PMTs (thin overlay, slurry seal, crack seal, document has been prepared in part with information collected under and chip seal) in fall 1990. The distress score concept used by the Texas the sponsorship of FHWA's Special Project 205, Quality Concrete Pave- Department of Transportation (TxDOT) was adopted in this study to ment Rehabilitation. Other documents to provide similar guidance in judge the effectiveness of PMTs. TxDOT has used this concept since the other CPR techniques will follow. early 1980s, though the utility factors have been revised a few times. The distress score quantifies the visible surface wear due to traffic and envi- Croteau, Jean-Martin, Peter Linton, J. Keith Davidson, and Gary ronmental influences. Only very few sections experienced premature Houston. Seal Coat Systems in Canada: Performances and Practice. failures on the SPS-3 sites in Texas. In many cases, superior underlying Presented at 2005 Annual Conference of the Transportation Associ- pavement conditions have been found. The chip seal has the most sites ation of Canada, Calgary, Alberta, 2005. in which it is rated the best performer. The chip seals performed well on This paper describes how seal coat systems have been used in Canada a wide range of pavement conditions. In fact, chip seals have the high- and other countries for many decades. In fact, the development of the est distress score for both high- and low-traffic areas. When initial cost seal coat system is closely associated with the increased usage of the is considered, crack seal provides the best alternative for low-traffic automobile. Today, seal coating it is the most common type of roadway routes that have a sound underlying pavement structure. For high-traffic surfacing in Canada. Seal coat is a thin wearing course made of super- routes, chip seal is a better choice. However, a thin overlay is the most imposed layers of aggregate and bituminous binder. This type of treat- effective for rut resistance. Since the thin overlay has the highest initial ment may be used to restore the surface characteristics of existing cost, it is best used on high-traffic routes where rutting is a major con- worn-out roadway or to waterproof and preserve an existing roadway. cern. If rutting is not a concern, chip seal is the best choice for a high- They may be applied onto an existing bound material or an unbound traffic area. The treatments applied to US84 sections were too late and road base. This type of treatment forms an impervious thin overlay over did not reach 7 years of life as normally was expected, which reconfirms an existing bound or unbound surface. Seal coat systems may be divided that the timing for PMT is important. into two families of treatments: the chip seal system and graded seal sys- tems. Chip seals combine the application of a layer of calibrated chips Chou, E. Y., D. Datta, and H. Pulugurta. Effectiveness of Thin Hot Mix onto a layer of a cationic rapid setting bitumen emulsion, whereas the Asphalt Overlay on Pavement Ride and Condition Performance. Report graded seals are systems that combine the application of a dense-graded FHWA/OH-2008/4. Ohio Department of Transportation, Columbus, or gap-graded aggregate onto a layer of anionic high float type bitumen Ohio, and FHWA, U.S. Department of Transportation, 2008. emulsion. Each system may be applied as a single application or a mul- The objectives of this study were (1) to determine the cost-effectiveness tiple application. Seal coat systems may be applied at spread rates that of thin hot-mix asphalt (HMA) overlays as a maintenance technique; (2) to determine under what conditions a thin overlay would be suit- range from 14 kg/m2 for a single chip seal applied onto an existing bitu- able; (3) to determine the timing of constructing a thin overlay to minous surface to 40 kg/m2 for a double high float seal treatment maximize its benefits; and (4) to develop a prototype aggregate source applied onto an unbound granular base. Many parameters, such as the information system to correlate aggregate source quality to pavement traffic and the existing surface conditions, must be considered in the performance. Performance data for thin overlays constructed by ODOT design of a specific seal coat system for a given roadway. Field adjustments since 1990 were collected to study the cost-effectiveness of thin overlay. are also important; field conditions such as ambient temperature, the The average thin overlay project cost is about 40% of the average minor time of the year, and the sun/cloud conditions must be taken into account rehabilitation project cost for the Priority System, and approximately as well. The success of this type of treatment is not only associated with 60% for the General System pavements. In contrast, the average service the selection of an optimal design but also with the close attention to life of a thin overlay is generally more than 70% of that of a minor reha- the local conditions during the field application. This paper presents bilitation. Therefore, most of the thin overlays are deemed cost-effective. an overview of the seal coating technologies and a discussion on the Thin overlay projects that are not cost-effective tend to be those per- state of the practice, including design practices and construction pro- formed on very poor pavements and with insufficient thickness. Thin cedures of these surface treatments in Canada and abroad. In addition, overlays are most likely to be cost-effective if the existing pavement's the paper introduces new concepts related to the selection of seal coat- PCR score is between 70 and 90 for Priority System and between 65 and ing systems as well as the emerging chip sealing systems now available 80 for General System pavements. A prototype aggregate source GIS in North America. system was developed. Higher aggregate soundness loss correlates with Cuelho, E., R. Mokwa, and M. Akin. Preventive Maintenance Treat- higher pavement deterioration rate. A thin HMA overlay is generally a ments of Flexible Pavements: A Synthesis of Highway Practice. Report cost-effective maintenance treatment. Employed properly, thin overlay FHWA/MT-06-009/8117-26. Montana Department of Transportation, provides a relatively low-cost alternative in preserving and extending Helena, Mont., and FHWA, U.S. Department of Transportation, 2006. the service life of the existing pavement. An extensive literature review was conducted to synthesize past and Correa, A. L., and B. Wong. Concrete Pavement Rehabilitation Guide ongoing research related to highway pavement maintenance and preser- for Diamond Grinding. Report FHWA-SRC-1/10-01(5M). FHWA, vation techniques. The literature review was augmented with a web- U.S. Department of Transportation, 2001. based e-mail survey that was distributed to all 50 states, Washington, This technical bulletin recommends procedures for selecting, design- D.C., and 11 Canadian provinces, for a total of 62 recipients. The litera- ing, and constructing diamond grinding in portland cement concrete ture review and survey results provide interesting qualitative overviews

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95 of the state of the practice of preventive maintenance treatments and Federal Highway Administration (FHWA) and Foundation for Pave- how these treatments are instigated, managed, and accessed by trans- ment Preservation (FP2). A Pocket Guide to Asphalt Pavement Preser- portation department personnel throughout North America. This report vation. Foundation for Pavement Preservation and FHWA, U.S. focuses on studies that quantified the performance of various preventive Department of Transportation, 2005. maintenance treatments, including the effect these treatments have on No abstract available. pavement performance. The study indicates that ranges of reported life Galehouse, L. Development of a Pavement Preventive Maintenance expectancies for treatment systems vary widely, as does reported unit Program for the Colorado Department of Transportation. Report costs. The lack of conclusive quantitative data is attributed to variations CDOT-DTD-R-2004-17. Colorado Department of Transportation. in the many aspects of treatment systems. Additional research is needed Denver, Colo., 2004. to quantify and enhance our understanding of the short- and long-term The National Center for Pavement Preservation was contracted to effects that treatment systems have on highway pavement surfaces. review the Colorado Department of Transportation's preventive main- State- or region-specific research is critically important to ensure that tenance program. Each region was visited to discuss various preventive funds are wisely used for extending the life of a pavement section or for maintenance treatments and examine current maintenance practices. repairing ailing pavement surfaces. Areas requiring further action before implementing a successful preven- Dunn, L., and S. Cross. Basic Asphalt Recycling Manual. Asphalt tive maintenance program were identified. This document contains field Recycling and Reclaiming Association, Annapolis, Md., 2001. reports for each of the six regions visited. Also included in this report are The growing demand on our nation's roadways over that past couple of Appendix A, Preventive Maintenance Program Guidelines, and Appen- decades, decreasing budgetary funds, and the need to provide a safe, effi- dix B, Distress Manual for HMA and PCC Pavements. cient, and cost-effective roadway system has led to a dramatic increase Galehouse, L., J. S. Moulthrop, and R. G. Hicks. Principles of Pave- in the need to rehabilitate our existing pavements. The last 25 years has ment Preservation: Definitions, Benefits, Issues, and Barriers. TR also seen a dramatic growth in asphalt recycling and reclaiming as a tech- News, No. 228, Sept.Oct., 2003, pp. 49. nically and environmentally preferred way of rehabilitating the existing Americans are accustomed to easy mobility on safe, smooth, and well- pavements. Asphalt recycling and reclaiming meets all of our societal maintained roads. These same roads play a critical role in the nation's goals of providing safe, efficient roadways, while at the same time dras- economy, bolstering agriculture, industry, commerce, and recreation. tically reducing both the environmental impact and energy (oil) con- During the 1990s, the nation's highways experienced a 29% increase in sumption compared to conventional pavement reconstruction. use, and growth is expected in the next 10 years. Large commercial truck Eltahan, A. A., J. F. Daleiden, and. A. L. Simpson. Effectiveness of Main- traffic increased by nearly 40%, with growth projected to continue at tenance Treatments of Flexible Pavements. Transportation Research more than 3% per year during the next 20 years. In addition, more than Record: Journal of the Transportation Research Board, No. 1680, TRB, 95% of personal travel is by automobile. Increasing the capacity of high- National Research Council, Washington, D.C., 1999, pp. 1825. ways, therefore, is important in meeting the nation's needs. But can the To achieve effective pavement maintenance, the life expectancy and United States finance future highway capacity while addressing the timing of treatment applications need to be determined. The Long- needs of the current system? Yes--by developing a strategic plan that Term Pavement Performance (LTPP) program includes the Specific includes pavement preservation. Pavement Study-3 (SPS-3), which focuses on this subject. The treat- ments applied are chip seals, crack seals, slurry seals, and thin overlays. Geiger, D. Memorandum: Pavement Preservation Definitions. FHWA, In studying the life expectancy, it is not feasible to wait for all the sec- U.S. Department of Transportation, 2005. www.fhwa.dot.gov/pave tions in the experiment to fail. Thus, there is a need to determine the life ment/preservation/091205.cfm. expectancy while making efficient use of the available data-collection No abstract available. funds. Survival data analysis is a statistical technique that meets this Geoffroy, D. N. NCHRP Synthesis of Highway Practice 223: Cost- need by accounting for the portion of the sections in which the exact Effective Preventive Pavement Maintenance. TRB, National Research time the treatment lasted is not known. The application of this tech- Council, Washington, D.C., 1996. nique to flexible-pavement maintenance is presented. In addition, some This synthesis will be of interest to highway agency executive manage- results of the LTPP SPS-3 experiment are presented to the highway ment, including administrative, budget, and finance personnel; pave- community. The focus is on the LTPP Southern Region (Alabama, ment design, construction, and maintenance engineers; and maintenance Arkansas, Florida, Mississippi, Oklahoma, Tennessee, and Texas). The operations personnel, including supervisors and maintenance crew lead- results showed that the probability of failure was two to four times ers. This synthesis describes the state of the practice with respect to set- higher for the sections that were in poor condition at the time the treat- ting a coherent strategy of cost-effective preventive maintenance for ment was applied than those sections that were in better condition. The extending pavement life. This report of the Transportation Research median survival times for thin overlays, slurry seals, and crack seals were Board describes the practices of state, local, and provincial transporta- 7, 5.5, and 5 years, respectively. The chip-seal sections had not yet reached tion agencies that are attempting to minimize the life-cycle costs of the 50% failure probability after 8 years of the SPS-3 experiment. Accord- pavements and are identifying, during the design of the pavement ingly, chip seals appear to have outperformed the other treatments inves- rehabilitation, reconstruction, or construction projects, the future tigated in this study in delaying the reappearance of distress. preventive maintenance treatments and the timing and funding for Federal Highway Administration (FHWA). 2002 Status of the Nation's those treatments. It includes a review of domestic literature and a sur- Highways, Bridges, and Transit: Conditions and Performance. Report vey of current practices in North America. The appendices include a FHWA-PL-03-003. FHWA, U.S. Department of Transportation, 2002. primer on pavement design and construction, the benefits of preven- The report provides Congress and other decision makers with an objec- tive maintenance of pavements, a summary of the questionnaire data tive appraisal of highway, bridge, and transit physical conditions; oper- collected, a simulation of pavement management strategies, and an ational performance; financing mechanisms; and future investment example process to demonstrate the cost-effectiveness of preventive requirements. maintenance.

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96 Gilbert, T. M., P. A. Olivier, and N. E. Gal. Ultra Thin Friction identifying and selecting the reliable and cost-effective rehabilitation Course: Five Years on in South Africa. Proc., 8th Conference on alternatives for existing HMA pavements. It addresses the rehabilitation Asphalt Pavements for Southern Africa (CAPSA'04), Sun City, South process for conventional HMA pavements in a logical sequence, from a Africa, 2004. detailed functional and structural evaluation of the existing pavement, In the past 5 years, ultra-thin friction course has been successfully paved to a needs assessment and development of feasible alternatives, to the on some of the heaviest trafficked national highways in South Africa, as selection of the preferred rehabilitation alternative. The course com- well as on other national routes, provincial highways, provincial rural bines lectures and workshop sessions to provide participants with roads, urban major and minor arterials, and urban industrial roads and hands-on experience with the techniques for HMA pavement rehabili- local roads. Ultra-thin friction coarse (UTFC) is ultimately a very thin tation. Although any individual associated with pavement rehabilita- asphalt layer paved at between 15 mm and 20 mm thick while spraying tion will benefit from this course, the primary audience is roadway a thick tack-coat to the road surface all in one pass. It has a number of design, construction, and maintenance engineers who are responsible functional properties and advantages over other conventional asphalt for developing and selecting an agency's pavement rehabilitation alter- paving procedures and products, which are mentioned later on in the natives. This reference manual contains four blocks of material. The paper. The essence of this paper describes the origin and history of first block contains an introduction to the course, as well as an intro- UTFC, its various applications over the past 5 years in South Africa, duction to HMA pavements. Block 2 discusses the pavement evaluation including the performance and nonperformance thereof, with recom- process, describing ways of evaluating and characterizing the condition mendations for future use in Southern Africa. of the existing HMA pavement. Block 3 presents key design and con- Gransberg, D. D. Chip Seal Program Excellence in the United States. struction information on common HMA pavement maintenance and Transportation Research Record: Journal of the Transportation rehabilitation activities, such as crack sealing, surface treatments, over- Research Board, No. 1933, Transportation Research Board of the lays, and recycling. Finally, Block 4 describes a methodology for select- National Academies, Washington, D.C., 2005, pp. 7282. ing the preferred rehabilitation alternative from a short list of feasible A survey of U.S. public highway and road agencies that use chip seals as alternatives, featuring the use of life-cycle cost analysis. Two other doc- a part of their roadway maintenance program was developed and con- uments accompany this reference manual for the training course. A par- ducted to identify best practices in chip seal design and construction. A ticipant's workbook has been developed to assist participants in following total of 72 individual responses from 42 states and 12 U.S. cities and the presentation of the course materials and to facilitate the comprehen- counties were received; of those, nine respondents reported that they sion of the information. It also contains the four workshop problems that were getting excellent results from their chip seal programs. Those are intended to enhance participants' understanding of the technical responses were grouped together and analyzed by the case study method material presented in the course. An instructor's guide has been assem- to identify trends that lead to consistently excellent chip seal results. The bled to assist instructors in presenting the training course, and it contains study found that the successful chip seal programs had much in com- supplemental notes on the presentation and workshop materials. mon. They use chip seals as a preventive maintenance tool, applying Hall, K. T., C. E. Correa, and A. L. Simpson. NCHRP Web Document them to roads before distress levels were classified as moderate. They 47: LTPP Data Analysis--Effectiveness of Maintenance and Rehabil- require their contractors to use the latest technology, and they exploit itation Options. Transportation Research Board of the National advances in materials science, such as the use of modified binders. And Academies, Washington, D.C., 2002. most of them use chip seals on both high- and low-volume roads. This report finds that overlay thickness and preoverlay roughness level Gransberg, D., and D. M. B. James. NCHRP Synthesis of Highway were the two factors that most influenced the performance of asphalt Practice 342: Chip Seal Best Practices. Transportation Research overlays of asphalt pavements. Board of the National Academies, Washington, D.C., 2005. Hein, D., and J. M. Croteau. The Impact of Preventive Maintenance This synthesis report provides an overview of successful chip seal prac- Programs on the Condition of Roadway Networks. Presented at 2004 tices in the United States, Canada, and overseas. Although not meant to Annual Conference of the Transportation Association of Canada, be an exhaustive study, it covers the spectrum of chip seal practice and Qubec City, Qubec, 2004. presents, where possible, the state of the art, as reported in the literature This paper describes the best practice for the use of thin surface restora- and survey responses. The report presents ways to assist in the devel- tion techniques for the preservation of bituminous pavements developed opment and implementation of pavement preservation programs by as a part of the Canadian National Guide for Sustainable Municipal identifying the benefits of using chip seal as part of a preventive main- Infrastructure (NGSMI). Thin surface restoration techniques are treat- tenance program. Innovative and advanced chip seal programs from ments applied to the pavement surface that increase pavement thickness around the world were identified with respect to critical factors that can by less than 40 mm. This distinction is made because overlays that are be incorporated by other transportation agencies. Approximately 40 best 40 mm thick or more are usually associated with routine paving opera- practices were identified in the areas of chip seal design methods, con- tions. The following treatments are described in this paper: (1) thin tract administration, equipment practices, construction practices, and hot-mix overlay (less than 40 mm); (2) hot-in-place recycling; performance measures. The increased use of chip seals for maintenance (3) microsurfacing; (4) slurry seal; (5) seal coat; (6) restorative seal; can be a successful, cost-effective way of using preventive maintenance and (7) texturization. Thin surface restoration techniques do not sig- to preserve both low-volume and higher-volume pavements. nificantly increase the strength of the pavement but benefit pavements Grogg, M., K. D. Smith, S. B. Seeds, T. E. Hoerner, D. G. Peshkin, and by protecting the pavement structure from premature deterioration or H. T. Yu. HMA Pavement Evaluation and Rehabilitation: Reference by improving or restoring the pavement surface. Thin pavement sur- Manual. National Highway Institute, FHWA, U.S. Department of face restoration techniques are also well suited as temporary treatments Transportation, 2001. until a permanent treatment can be implemented. The benefits of using This document serves as the reference manual for the FHWA/NHI thin surface restoration techniques can be realized in several ways. The training course HMA Pavement Evaluation and Rehabilitation. The paper describes the technology of thin surface restoration techniques for course provides detailed information to assist pavement engineers in bituminous pavements, including materials and construction techniques,

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97 expected service life and costs, surface preparation requirements, benefit from this course, the primary audience is roadway design, detailed procedures for choosing between alternative treatments, exam- construction, and maintenance engineers who are responsible for devel- ples of use by Canadian municipalities, potential challenges, and new oping and selecting an agency's pavement rehabilitation alternatives. developments. The use of thin surface restoration techniques promotes This reference manual contains four blocks of material. The first block the use of preventive maintenance for pavement preservation. It describes contains an introduction to the course, as well as an introduction to PCC how to use thin surface restoration techniques as preventive maintenance pavements. Block 2 discusses the pavement evaluation process, describ- treatments, and provides guidelines on how to incorporate the use of ing ways of evaluating and characterizing the condition of the existing these treatments into existing pavement management procedures. Pro- PCC pavement. Block 3 presents key design and construction informa- vided in this paper are guidelines for the systematic evaluation of the tion on common PCC pavement maintenance and rehabilitation activ- performance of new treatments. The use of thin surface restoration tech- ities, such as crack sealing, surface treatments, overlays, and recycling. niques should be part of the pavement preservation toolbox of all munic- Finally, Block 4 describes a methodology for selecting the preferred ipal agencies. rehabilitation alternative from a short list of feasible alternatives, fea- turing the use of life cycle cost analysis. Two other documents accom- Hicks, R. G. Treatment Selection for Flexible Pavements. Presented pany this reference manual for the training course. A participant's at California Pavement Preservation Conference, Newport Beach, workbook has been developed to assist participants in following the Calif., 2008. presentation of the course materials and to facilitate the comprehen- No abstract available. sion of the information. It also contains the four workshop problems Hicks, R. G., and R. Marsh. Pavement Preservation Sub-Group on that are intended to enhance participants' understanding of the tech- Strategy Selection and Evaluation. Presentation to Caltrans, 2005. nical material presented in the course. An instructor's guide has been www.dot.ca.gov/hq/maint/PavePres/04pptg.pdf. assembled to assist instructors in presenting the training course, and No abstract available. it contains supplemental notes on the presentation and workshop materials. Hicks, R. G., S. B. Seeds, and D. G. Peshkin. Selecting a Preventive Maintenance Treatment for Flexible Pavements. Presented at Foun- Huddleston, I. J., H. Zhou, and R. G. Hicks. Evaluation of Open- dation for Pavement Preservation Conference, 1999. Graded Asphalt Concrete Mixtures Used in Oregon. Transportation No abstract available. Research Record 1427, TRB, National Research Council, Washington, D.C., 1993, pp. 512. Hicks, R. G., S. B. Seeds, and D. G. Peshkin. Selecting a Preventive Maintenance Treatment for Flexible Pavements. Report FHWA-IF- Open-graded friction course (OGFC) is characterized by the use of large 00-027. Foundation for Pavement Preservation (FP2), Washington, percentage of coarse aggregate in the mix without a significant propor- D.C., and FHWA, U.S. Department of Transportation, 2000. tion of fines as commonly found in dense-graded mix. In an attempt to Maintenance engineers have been applying treatments to both flexible assess the performance of the open-graded mixes, a survey was made of and rigid pavements for as long as such pavements have existed. The some of the older OGFC projects and their performance was compared types and application of various treatments for both corrective and pre- to projects paved with dense-graded asphalt concrete mixes. The eval- ventive maintenance have been the subject of research studies over a uation demonstrated that all of the open-graded projects had improved number of years, and many publications have reported these findings. performance when compared to dense-graded projects. This included: Recently, the Federal Highway Administration (FHWA) has initiated an resistance to cracking, a slightly increased resistance to rutting, and effort to encourage DOTs (state and local) to begin, or extend, the prac- improved skid gradient. The evaluation supports the continued use of tice of preventive maintenance, since there simply is not enough money open-graded mixture and additionally, the assessment provided the available to continue the types of maintenance currently employed. This opportunity to develop new and improved guidelines for the use of report specifically addresses flexible pavement preventive maintenance, those mixes. including the types of pavements that are candidates for preventive Illinois Department of Transportation (Illinois DOT). Chapter 52: maintenance, the available treatments, where and when they should Pavement Preservation. Design and Environment Manual. Illinois be used, their cost-effectiveness, the factors to be considered in selecting DOT, Springfield, Ill., 2009. the appropriate treatment strategy, and a methodology to determine the The manual has been prepared to provide uniform practices for the most effective treatment for a particular pavement. department and consultant personnel preparing Phase I studies and Hoerner, T. E., K. D. Smith, H. T. Yu, D. G. Peshkin, and M. J. Wade. reports and contract plans for department projects. The manual pre- PCC Pavement Evaluation and Rehabilitation: Reference Manual. sents most of the information normally required in the development of National Highway Institute, FHWA, U.S. Department of Transporta- a typical roadway project. The designer should attempt to meet all cri- tion, 2001. teria and practices presented in the manual; however, the manual This document serves as the reference manual for the FHWA/NHI should not be considered a standard that must be met regardless of training course PCC Pavement Evaluation and Rehabilitation. The impacts. The designer should develop roadway designs that meet the course provides detailed information to assist pavement engineers in department's operational and safety requirements while preserving the identifying and selecting the reliable and cost-effective rehabilitation aesthetic, historic, or cultural resources of an area. Designers must exer- alternatives for existing PCC pavements. It addresses the rehabilitation cise good judgment on individual projects and, frequently, they must process for conventional PCC pavements in a logical sequence, from a be innovative in their approach to roadway design. This may require, detailed functional and structural evaluation of the existing pavement, for example, additional research into the highway literature. to a needs assessment and development of feasible alternatives, to the selection of the preferred rehabilitation alternative. The course com- International Grinding and Grooving Association (IGGA). Rigid Pave- bines lectures and workshop sessions to provide participants with hands- ment Distress and Strategy Selection. Presented at 2009 California on experience with the techniques for PCC pavement rehabilitation. Pavement Preservation Conference, Oakland, 2009. Although any individual associated with pavement rehabilitation will No abstract available.

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98 Jackson, N., and J. Puccinelli. Long-Term Pavement Performance seal coat design process based on the McLeod method and guidance on (LTPP) Data Analysis Support: National Pooled Fund Study TPF- seal coat aggregates and binders. An update on the use of local aggre- 5(013)--Effects of Multiple Freeze Cycles and Deep Frost Penetration gates for microsurfacing in Iowa is included. Winter maintenance on Pavement Performance and Cost. Report FHWA-HRT-06-121. guidelines for thin maintenance surfaces are also reported. Finally, FHWA, U.S. Department of Transportation, 2006. Phase 1's interim, qualitative thin maintenance surface guidelines are The objectives of this study are to (1) quantify the effects of frost penetra- supplemented with Phase 2's revised, quantitative guidelines. When tion on pavement performance in climates with deep, sustained frost as thin maintenance surfaces are properly selected and applied, they can compared to environments with multiple freeze-thaw cycles; (2) investi- improve the pavement surface condition index and the skid resistance gate the effect that local adaptations have on mitigating frost penetration of pavements. For success to occur, several requirements must be met, damage; and (3) estimate the associated cost of constructing and main- including proper material selection, design, application rate, workman- taining pavements in freezing climates. The approach consisted of mod- ship, and material compatibility, as well as favorable weather during eling various pavement performance measures using both climatic and application and curing. Specific guidance and recommendations for nonclimatic input variables and performance data collected as part of many types of thin maintenance surfaces and conditions are included the Long-Term Pavement Performance program. Five climatic scenar- in the report. ios are defined in terms of climatic input variables for the models. Pre- Johnson, A. M. Best Practices Handbook on Asphalt Pavement Main- dicted performance measures are presented for each of the climatic tenance. Report MN/RC-2000-04. University of Minnesota Center for scenarios and compared at a 95% confidence interval to determine sta- Transportation Studies, Minneapolis, Minn., 2000. tistically significant performance differences. Participating pooled-fund The purpose of this handbook is to provide background information states (PFS) were queried as to standard specifications, standard designs, about the importance of pavement preservation and preventive mainte- average life expectancies, and construction costs specific to each state nance, as well as present maintenance techniques for a variety of distresses highway agency (SHA). These data, along with information acquired and conditions. The major focus of this handbook is on preventive main- through literature review of SHA standard practices, are summarized tenance activities, which are performed while the roadway is still in good with consideration given to the mitigation of frost-related damage. Life- condition with only minimal distress, before the pavement falls into a cycle cost analysis for each climatic scenario using predicted perfor- condition where structural overlays, major milling or reclaiming, or mance to determine average life and average agency construction costs for replacement is necessary. The most common flexible pavement dis- standard pavement sections is also discussed and compared. The use of tresses are cracking, roughness, weathering, raveling, rutting, and bleed- the performance models for local calibration as required in the National ing. If the distresses identified in a pavement are related to structural Cooperative Highway Research Program Guide for Mechanistic-Empirical deficiencies, the pavement section is most likely not a candidate for Design of New and Rehabilitated Pavement Structures is explored along preventive maintenance treatment, and should be scheduled for reha- with the possible application of the performance models in pavement bilitation or reconstruction. Maintenance treatments covered in this management systems. handbook include crack repair with sealing, including clean and seal, Jahren, C. T., K. L. Bergeson, A. Al-Hammadi, S. Celik, G. Lau, and saw and seal, and rout and seal; crack filling; full-depth crack repair; H. Quintero. Interim Guidelines for Thin Maintenance Surfaces in fog seal; seal coat; double chip seal; slurry seal; microsurfacing; thin Iowa. Proc., 2000 Mid-Continent Transportation Research Sympo- hot-mix overlays; and potholes and pavement patching. Tables are sium, Center for Transportation Research and Education, Iowa State outlined giving the most common flexible pavement distresses, along University, Ames, Iowa, 2000. with the best practices for rehabilitation for each. Also given are rec- The first phase of a two-phase research project was conducted to ommended applications for crack sealers and fillers, surface treat- develop guidelines for Iowa transportation officials on the use of thin ments, and pothole patching. Specifications, technical memoranda and maintenance surfaces (TMS) for asphaltic concrete and bituminous special provisions are included for all treatment methods recommended roads. Thin maintenance surfaces are seal coats (chip seals), slurry seals, in the handbook. and microsurfacing. Interim guidelines were developed to provide Kandhal, P. S., and R. B. Mallick. Pavement Recycling Guidelines for guidance on which roads are good candidates for TMS, when TMS State and Local Governments: Participant's Reference Book. Report should be placed, and what type of thin maintenance surface should be FHWA-SA-98-042. FHWA, U.S. Department of Transportation, 1997. selected. The guidelines were developed specifically for Iowa weather, Recycling or reuse of existing asphalt pavement materials to produce traffic conditions, road-user expectations, and transportation official new pavement materials has the following advantages: reduced costs of expectations. construction, conservation of aggregate and binder, preservation of the Jahren, C. T., W. A. Nixon, and K. L. Bergeson. Thin Maintenance existing pavement geometrics, preservation of the environment, and Surfaces: Phase Two Report with Guidelines for Winter Maintenance conservation of energy. This document was prepared to provide the on Thin Maintenance Surfaces. Project TR-435. Iowa Department of following information on recycling of asphalt pavements: performance Transportation and Iowa Highway Research Board, 2003. data, legislation/specification limits, selection of pavement for recy- In recent years, there has been renewed interest in using preventive cling and recycling strategies, economics of recycling, and structural maintenance techniques to extend pavement life and to ensure low life- design of recycled pavements. The following recycling methods have cycle costs for Iowa's road infrastructure network. Thin maintenance been included: hot-mix asphalt recycling (both batch and drum surfaces can be an important part of a preventive maintenance program plants), asphalt surface recycling, hot in-place recycling, cold-mix for asphalt cement concrete roads. The Iowa Highway Research Board asphalt recycling, and full depth reclamation. Materials and mix has sponsored Phase 2 of this research project to demonstrate the use of design, construction methods and equipment, case histories and qual- thin maintenance surfaces in Iowa and to develop guidelines for thin ity control/quality assurance have been discussed for all recycling maintenance surface uses that are specific to Iowa. This report docu- methods. This participant's reference book was developed to support ments the results of test section construction and monitoring started in a 2-day workshop on pavement recycling guidelines for state and local Phase 1 and continued in Phase 2. The report provides a recommended governments.

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99 Kentucky Transportation Cabinet (KYTC). Pavement Management long-term cost-effectiveness of two competing pavement treatments Field Handbook: KYTC Pavement Distress Identification Manual and using three measures of effectiveness (MOE)--treatment service life, Guideline for Preventive Maintenance Treatments. KYTC, Frankfort, increase in average pavement condition, and area bounded by the per- Ky., 2009. formance curve--and two measures of cost--agency cost only and total Each year the Operations and Pavement Management Branch performs cost (agency plus user costs). Only non-Interstate pavement sections are detailed pavement condition evaluations of all Interstate and parkway considered in the study, and each MOE is expressed in terms of inter- pavements and one-third of the remaining system (state primary, state national roughness index (IRI) values. For all measures of treatment secondary, and supplemental roads). The evaluations are used to docu- effectiveness where costs are expressed only in terms of agency cost irre- ment roadway deterioration, recommend pavement rehabilitation treat- spective of climate severity and traffic loading, it was found that micro- ments, and prioritize projects. In order for evaluation data to be useful surfacing is consistently more cost-effective compared with thin HMA for predictive measures, consistent methods of distress identification overlays. An exception occurs when increase in pavement condition is and recording are critical. The Pavement Distress Identification Manual used as the MOE and when both traffic volume and climate severity are will foster more uniform and consistent pavement distress evaluations high. Under these conditions, thin HMA overlay appears to be more by providing identification definitions and guidelines. The manual is cost-effective. The superiority of microsurfacing in terms of cost is most intended to be a training aid for pavement raters and a field reference evident when treatment life is the measure of effectiveness that is used during the rating process. The manual can also be used with completed and least evident when increased pavement condition is used. Micro- evaluations to describe the typical condition of a roadway section. surfacing also appears to be more cost-effective under low traffic load- ing and low climatic severity. The study methodology results offer Koch Materials Company (Koch). Innovation for Performance. Pre- significant implications in the field of pavement design, engineering, sentation. 2001. www.pavementpreservation.org/library/getfile.php? and management. Highway agencies are continuously striving to journal_id=201. develop decision trees and matrices for intervention, and it is sought to No abstract available. carry out these tasks on the basis of rational cost and effectiveness analy- Kuennen, T. Making High-Volume Roads Last Longer. In Pavement sis rather than subjective opinion. The development of such decision Preservation Compendium II, Publication FHWA-IF-06-049, FHWA, mechanisms can facilitate the design of preventive maintenance strate- U.S. Department of Transportation, 2006, pp. 3644. www.fhwa.dot gies for more cost-effective decisions that are based on life-cycle costs .gov/pavement/preservation/ppc06.pdf. and benefits. This article reports on techniques to preserve high-volume roads so Lamptey, G., S. Labi, M. Ahmad, and K. Sinha. Life Cycle Cost Analysis they last longer. The techniques--crack sealing, chip seals, slurry sur- for INDOT Pavement Design Procedures. Report FHWA/IN/JTRP- facings, and overlays--are the same as those that are standard for low- 2004/28. Joint Transportation Research Program, Indiana Department volume, secondary roads. But they need precision applications and of Transportation and Purdue University, West Lafayette, Ind., 2005. disciplined choice of tactics to succeed. Instead of intuitively timed Given the aging of highway pavements, high traffic levels, and uncer- applications of off-the-shelf materials for a chip and seal repair, the tainty of sustained preservation funding, there is a need for balanced same type of repair for a high-volume road will be designed in a labo- decision-making tools such as life-cycle cost analysis (LCCA) to ensure ratory based on existing conditions, climate, and traffic loads, with a long-term and cost-effective pavement investments. With driving binder and chip that are tailored to the demands of that particular pave- forces such as Intermodal Surface Transportation Efficiency Act of 1991 ment. When properly designed and judiciously applied, they can out- (ISTEA), the National Highway System (NHS) Act of 1995, and the perform the standard, more costly asphalt overlay after years of minimal Transportation Equity Act for the 21st Century (TEA-21), LCCA enables care. The changes comes after the advent of the Strategic Highway evaluation of overall long-term economic efficiency between competing Research Program (19881993), which demonstrated that high-volume alternative investments and consequently has important applications in roads can benefit from this sort of attention. The article includes a list pavement design and management. It has been shown in past research of preservation methods developed by FHWA and descriptions of a few that more effective long-term pavement investment could be made at specific projects. lower cost using LCCA. Current LCCA-based pavement design and Kuennen, T. Pavement Preservation: Techniques for Making Roads preservation practice in Indiana could be further enhanced by due con- Last. In Pavement Preservation Compendium II, Publication FHWA- sideration of user costs. Also, the existing FHWA LCCA software could IF-06-049, FHWA, U.S. Department of Transportation, 2006, pp. 1214. be further enhanced for increased versatility, flexibility, and more spe- www.fhwa.dot.gov/pavement/preservation/ppc06.pdf. cific applicability to the needs of Indiana, particularly with regard No abstract available. to treatment cost estimation and development of alternative feasible preservation strategies (rehabilitation and maintenance types and tim- Kuennen, T. When Prevention is the Cure. In Pavement Preservation ings). The study documented and developed several sets of alternative Compendium II, Publication FHWA-IF-06-049, FHWA, U.S. Depart- pavement design and preservation strategies consistent with existing ment of Transportation, 2006, pp. 8691. www.fhwa.dot.gov/pave and foreseen Indiana practice. The preservation strategies were devel- ment/preservation/ppc06.pdf. oped using two alternative criteria--trigger values (pavement condition No abstract available. thresholds) and predefined time intervals (based on treatment service Labi, S., M. Mahmodi, C. Fang, and C. Nunoo. Cost-Effectiveness of lives)--and are intended for further study before they can be used for Microsurfacing and Thin Hot-Mix Asphalt Overlays: Comparative practice. These strategies were developed on the basis of historical pave- Analysis. Presented at 86th Annual Meeting of the Transportation ment management data, existing Indiana Department of Transporta- Research Board, Washington, D.C., 2007. tion (INDOT) Design Manual standards, and a survey of experts. The Microsurfacing and thin hot-mix asphalt (HMA) overlays are cate- study also found that with a few enhancements, FHWA's current LCCA gories of flexible pavement preventive maintenance that involve an methodology and software (RealCost) could be adapted for use by aggregate-bituminous mix laid over the entire carriageway width. This INDOT for purposes of decision support for pavement investments and paper presents and demonstrates a methodology for comparing the proceeded to make such enhancements. The resulting software product

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100 (RealCost-Indiana) is more versatile, flexible, and specific to Indiana resulted: (a) the rigid pavement portion of the software was calibrated practice. The enhancements made include a mechanism by which the successfully; (b) WSDOT pavements require calibration factors sig- user can estimate the agency cost of each pavement design or preserva- nificantly different from default values; (c) the software does not tion activity on the basis of line items and their unit rates, and a set of model longitudinal cracking, which is significant in WSDOT pavements; menus showing default or user-defined strategies for pavement preser- (d) WSPMS does not separate longitudinal and transverse cracking, vation. Other enhancements made to the software include improved a lack that makes calibration of the software's transverse cracking graphics, enhanced reporting of analysis results, and capability to model difficult; and (e) the software does not model studded tire wear, simultaneously carry out analysis for more than two pavement design which is significant in WSDOT pavements. Results indicate that the and preservation alternatives. A user manual was prepared to facilitate calibrated software can be used to predict future deterioration caused the use of the enhanced software, and a technical manual was prepared by faulting, but it cannot be used to predict cracking caused by the to provide for the user a theoretical basis for various concepts used in transverse or longitudinal crack issues. the software. The enhanced LCCA methodology and software are use- ful for (1) identifying alternative INDOT pavement designs, (2) identi- Morian, D. A., J. A. Epps, and S. D. Gibson. Pavement Treatment fying or developing alternative strategies for pavement rehabilitation Effectiveness, 1995 SPS-3 and SPS-4 Site Evaluations, National and maintenance for a given pavement design, (3) estimating the life-cycle Report. Report FHWA-RD-96-208. FHWA, U.S. Department of Trans- agency and user costs associated with a given strategy, and (4) compara- portation, 1997. tive evaluation of alternative pavement designs. The enhanced methodol- This report presents an evaluation of the performance of Strategic ogy and software are applicable to existing pavements in need of some Highway Research Program (SHRP) SPS-3 and SPS-4 experiment sites rehabilitation treatment, and also for planned (new) pavements. Future based on field reviews after 5 years of performance. Condition evalua- enhancements to the LCCA methodology and software may include a way tion of the sections and Expert Task Group performance estimates are to duly penalize parsimonious preservation strategies that are presently the basis for treatment assessments. not adequately penalized for their resulting inferior pavement condition Morian, D. A., S. D. Gibson, and J. A. Epps. Maintaining Flexible over the life cycle. Pavements--The Long Term Pavement Performance Experiment: SPS-3 5-Year Data Analysis. FHWA-RD-97-102. FHWA, U.S. Depart- Li, J., J. Mahoney, S. Muench, and L. Pierce. Bituminous Surface ment of Transportation, 1998. Treatment Protocol for the Washington State Department of Trans- The Strategic Highway Research Program developed and coordinated portation. Presented at 87th Annual Meeting of the Transportation construction of test sections for flexible pavement maintenance through- Research Board, Washington, D.C., 2008. out the United States and Canada. Test sites included specific test sections To help the Washington State Department of Transportation (WSDOT) for evaluation of the performance of crack sealing, slurry seals, chip seals, enhance its pavement preservation program through an improved and thin hot-mix overlays as maintenance treatments. Each site also understanding of the use of bituminous surface treatment (BST), the included an untreated control section. This report discusses the project Highway Development and Management System (HDM-4) was used as background and analysis of monitoring data collected over a 5-year an analytical tool to test the AADT and equivalent single-axle load period by the Long-Term Pavement Performance project at SPS-3 sites (ESAL) levels appropriate as criteria for selecting the application of BST throughout the United States and Canada. The analysis considers three resurfacings to WSDOT pavements. It verified the feasibility of using important characteristics of the maintenance treatments: treatment BSTs to maintain pavements with higher traffic levels than have been performance, timing of application, and cost-effectiveness. In addition applied in the past. Results also suggested that alternating the applica- to data analysis results, the report conclusions include information tion of BST resurfacings and 45-mm hot-mix asphalt (HMA) overlays from Pavement Treatment Effectiveness, 1995 SPS-3 and SPS-4 Site Eval- is an effective rehabilitation strategy. Finally, the study results were used uations, National Report (May 1997). to estimate the impacts that increased use of BST surfaces would have on the performance of the state-owned route system. Morian, D. A., J. W. Mack, and T. Chowdhury. The Role of Pavement Preservation in Privatized Maintenance. In Transportation Research Li, J., S. T. Muench, J. P. Mahoney, L. M. Pierce, and N. Sivaneswaran. Circular E-C078: Roadway Pavement Preservation 2005, Transporta- Calibration of the Rigid Pavement Portion of the NCHRP 1-37A Soft- tion Research Board of the National Academies, Washington, D.C., ware for Use by the Washington State Department of Transportation. 2005, pp. 173183. http://onlinepubs.trb.org/onlinepubs/circulars/ Transportation Research Record: Journal of the Transportation ec078.pdf. Research Board, No. 1949, Transportation Research Board of the The concept of privatized maintenance took hold in the late 1980s when National Academies, Washington, D.C., 2006, pp. 4353. the Virginia Department of Transportation awarded the first such A significant amount of Washington State Department of Transporta- contract, and within 2 years a second contract, for the preservation of tion (WSDOT) portland cement concrete (PCC) pavement that was 350 centerline miles of Interstate highways 95 (I-95), I-77, and I-81 in placed in the 1960s is nearing the end of its serviceable life and must Virginia. The idea of these privatized maintenance contracts was to pro- soon be rehabilitated or replaced. Initial WSDOT estimates place the vide the contractor a fixed level of funding, and to establish a minimum cost of the anticipated work at more than $600 million. A tool to pre- pavement performance level that had to be maintained. While some dict PCC pavement deterioration and ultimate failure is needed to pri- sections required rehabilitation work, maximizing the use of pavement oritize rehabilitation and reconstruction efforts best. The software preservation strategies for suitable pavement sections is a key to success- associated with NCHRP Project 1-37A was chosen as a promising tool fully managing a pavement system with fixed funds. This paper discusses worthy of assessment for this application. The urgency of the situation the application of pavement preservation strategies, such as timely crack necessitated its use, despite the lack of formal calibration guidance, sealing, chip seals, and microsurfacing, and the valuable role pavement some software bugs, and isolated model inconsistencies. A procedure preservation has played in achieving the pavement performance and was developed and used to calibrate the rigid pavement portion of budget management objectives of privatized maintenance contracts. The the NCHRP 1-37A software to data obtained from the Washington discussion includes criteria for identifying the appropriate application State Pavement Management System (WSPMS). Significant findings of specific pavement preservation treatments. Pavement performance

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101 monitoring information from the project pavement management sys- in the driving-lane wheel paths. As a result, a milling technique for rut tem is also provided, documenting the success of these treatments in removal was used to rehabilitate this stretch of highway. The intended preserving pavement condition level in a cost-effective manner, while benefits were to improve the ride and texture of the surface and enhance at the same time providing an excellent tool for cash flow management. safety by removing areas of potential water ponding. Different milling techniques were evaluated to identify the most effective method of Morian, D. A., J. Oswalt, and A. Deodhar. Experience with Cold In- achieving the desired results. Fine tooth milling was finally selected as Place Recycling as a Reflective Crack Control Technique: Twenty the best available milling method for this stretch of highway. Rut, noise, Years Later. Transportation Research Record: Journal of the Trans- and ride or international roughness index (IRI) were measured and portation Research Board, No. 1869, Transportation Research Board analyzed, while the pavement distress index (PDI) values were extracted of the National Academies, Washington, D.C., 2004, pp. 4755. from WisDOT historical data. Measured rut values on the milled sur- Cold in-place recycling (CIR) of existing hot-mix asphalt materials has faces indicated minor rutting up to the third year after milling. The rut- been an available treatment for more than 20 years. A study evaluated ting progressively deteriorated up to the sixth year when the highway the performance of CIR projects and materials over that period. Con- was fine-tooth milled a second time. PDI slightly decreased after tractors in northwestern Pennsylvania have constructed a total of milling, but in less than 1 year, became similar to the results obtained 44 pavement sections. Ninety additional sections have been recycled as prior to milling. As a result, the district responsible for this stretch of part of maintenance activities. (The latter are not included among the highway recommended that subsequent fine tooth milling include ade- study sections.) A subset of these projects has been evaluated to deter- quate crack treatment. Ride as measured by IRI did not show any signif- mine performance characteristics and cost-effectiveness of the treat- icant differences between pre- and postrut milling. Noise measurements ment and the material. The treatment is used typically on rehabilitation indicated that the fine tooth milling does not affect significantly the inte- projects of roadways with 8,000 average daily traffic (ADT) or less but rior and exterior average noise levels. The noise measuring equipment has been used on projects with up to 13,000 ADT. The performance of used, however, may not have isolated the discrete tone referred to as CIR in resisting reflective cracking from underlying concrete pavements "whine," which is objectionable to auditory senses. Hence, the noise and material properties over time is discussed. Material layer stiffness measurement results may be inconclusive. Cost analysis, based on Wis- was evaluated using back-calculation of deflection measurement DOT bid tabulations, and using the equivalent uniform annual cost methods. Additionally, the cost of constructing these rehabilitation method, showed that resurfacing would cost about 14 times more than projects and their average cost-effectiveness are discussed. milling without crack treatment and 10 times more with crack treatment. National Cooperative Highway Research Program (NCHRP). Synthe- Available results, therefore, indicate that fine tooth milling is a viable sis of Highway Practice Topic 24-10: Asphalt Surface Treatments and rehabilitation technique for PCC pavements with AC overlay that has Thin Overlays. Unpublished Report. TRB, National Research Council, experienced premature rutting. It is a recommended treatment for use on Washington, D.C., 1997. this type of pavement when the desired service life is 6 years or less; how- No abstract available. ever, caution and judgment should be exercised on using this technique on older, more "brittle" pavements. New York State Department of Transportation (NYSDOT). Pave- ment Preservation Strategy. PowerPoint Presentation. NYSDOT, Page, G. C. Open-Graded Friction Courses: Florida's Experience. Albany, N.Y., 2008. Transportation Research Record 1427, TRB, National Research Coun- No abstract available. cil, Washington, D.C., 1993, pp. 14. The Florida Department of Transportation began its development of Newcomb, D. E. Information Series 135: Thin Asphalt Overlays for open-graded mixes in 1970 to provide improved wet-weather vehicular Pavement Preservation. National Asphalt Pavement Association, safety. Florida's FC-2 open-graded friction course is currently required Lanham, Md., 2009. for all multilane primary and Interstate highways of which the design No abstract available. speed is greater than 72 km/hr (45 mph). This mix uses locally available Ohio Department of Transportation (ODOT). ODOT Pavement Pre- aggregates and is produced at a reasonable cost. Changes and additions ventive Maintenance Guidelines. ODOT, Columbus, Ohio, 2001. to specification criteria have been made over the years to address unde- Preventive maintenance (PM) is a planned strategy of cost-effective sirable results. Maintenance, rehabilitation techniques, and improved treatments to an existing roadway system and its appurtenances that performance are being studied. Asphalt additives show promise to preserves the system, retards future deterioration, extends the service increase the design life of open-graded mixes. life, and maintains or improves the functional condition of the system Peshkin, D. G. Selecting a Preventive Maintenance Treatment for without substantially increasing structural capacity. Pavement PM treat- Flexible Pavements. Brochure. SemMaterials, Tulsa, Okla., 2000. ments reduce the amount of water infiltrating the pavement structure, No abstract available. protect the pavement system, slow the rate of deterioration, or correct Peshkin, D. G., and T. E. Hoerner. Pavement Preservation: Practices, surface deficiencies such as roughness and non-load-related distress. Research Plans, and Initiatives. Final Report, NCHRP Project 20-07, These treatments contribute little or no improvement to the pavement Task 184. Transportation Research Board of the National Academies, structure. They are not applicable and should never be applied if fatigue- Washington, D.C., 2005. http://maintenance.transportation.org/ related distress exists in the pavement. Documents/NCHRP20-07184FinalReport.pdf. Okpala, D., R. Schimiedlin, and S. Shober. Fine Tooth Milling Treatment This report identifies and documents pavement preservation research of Rutted Asphaltic Concrete Pavements. Report WI-13-99. Wisconsin needs. The primary sources of information used to develop this report Department of Transportation. Madison, Wis., 1999. include a comprehensive survey of state highway agency (SHA) practice The Portland cement concrete (PCC) pavement on Interstate I-94 and a review of recent literature on the topic. SHAs and four Canadian between the Minnesota state line and Osseo, Wisconsin, was resurfaced provinces were asked to provide detailed responses to a 33-question with asphalt concrete (AC) between 1983 and 1990. The section com- survey; the 35 responses that were received are viewed as an accurate pleted between 1983 and 1986 showed early signs of distress with rutting representation of the current state of the practice.

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102 Peshkin, D. G., T. E. Hoerner, and K. A. Zimmerman. NCHRP Report find its content to be of interest and value. The course presentation is No 523: Optimal Timing of Pavement Preventive Maintenance Treat- divided into nine distinct sessions: Introduction and Course Overview, ment Applications. Transportation Research Board of the National Components of Preventive Maintenance Programs, How Pavements Academies, Washington, D.C., 2004. Perform, Selecting the Right Pavement, Preventive Maintenance Treat- This report describes a methodology for determining the optimal tim- ments, Preventive Maintenance Treatment Timing and Project Selec- ing for the application of preventive maintenance treatments to flexible tion, The "Best" Treatment, Integrating Preventive Maintenance and and rigid pavements. The methodology is also presented in the form of Pavement Preservation, and Course Wrap-Up and Evaluation. It is a macro-driven Microsoft Excel Visual Basic Application--designated taught over the course of two 8-hour days, and includes many group OPTime--available to users by accessing the National Cooperative activities to present the course content and to improve the learning Highway Research Program (NCHRP) website (http://trb.org/news/ experience of participants. blurb_detail.asp?id=4306). The methodology is based on the analysis of Rao, S. P., H. T. Yu, and M. I. Darter. The Longevity and Performance performance and cost data and applies to any of the treatments and of Diamond-Ground Pavements. Portland Cement Association, Skokie, application methods that are used by highway agencies. A plan for con- Ill., 1999. structing and monitoring experimental test sections is also provided to Diamond grinding restores a smooth riding surface with desirable fric- assist highway agencies in collecting the necessary data if such data are tion characteristics on concrete pavements. This technique was first not readily available. The report is a useful resource for state and local used in 1965 on a 19-year-old section of I-10 in southern California to highway agency personnel and others involved in pavement mainte- eliminate excessive faulting. Since then, diamond grinding has become nance and preservation. an important element of concrete pavement restoration. The study Peshkin, D. G., K. D. Smith, K. A. Zimmerman, and D. N. Geoffroy. involved conducting a comprehensive review of existing information Pavement Preventive Maintenance: Reference Manual. Publication on diamond grinding, data collection, data analysis, and documenta- FHWA-HI-00-004. National Highway Institute, FHWA, U.S. Depart- tion of the study findings. Extensive field surveys were conducted to ment of Transportation, 1999. obtain the performance data needed for the analysis. In all, 60 pavement This document serves as the participant's reference manual for a FHWA/ sections in 18 states were surveyed. In addition, performance data for NHI training course on pavement preventive maintenance. Preventive 133 sections were obtained from an earlier study of the performance of maintenance, often summed up as "applying the right treatment to the diamond ground pavements. The data from the Long-Term Pavement right pavement at the right time," is becoming increasingly popular in Performance sections (concrete pavement rehabilitation) were also highway agencies interested in overall pavement preservation. The used to conduct direct side-by-side comparisons of the performance of objectives of this manual and course are to introduce the components diamond-ground pavement sections and other rehabilitation alterna- of a pavement preventive maintenance program, to define potential tives. Various analyses were conducted to document the performance treatment techniques and materials, to describe the relationship between of diamond-ground pavements, including an evaluation of faulting pavement management and pavement preventive maintenance, and to performance, longevity of diamond-ground texture, and the effects explain cost/benefit concepts of preventive maintenance to decision of diamond grinding on service life. Diamond-ground surfaces were makers. The material is organized into seven modules that are intended demonstrated to provide several years of service. No evidence of any to meet the above-stated objectives. The first module is an overview of deleterious effects of diamond grinding was observed at any field site. pavement preventive maintenance. This is followed by background Raza, H. An Overview of Surface Rehabilitation Techniques for information on the current status of preventive maintenance, appropri- Asphalt Pavements. Report FHWA-PD-92-008. FHWA, U.S. Depart- ate definitions, objectives of preventive maintenance programs, and ment of Transportation, 1992. barriers to success. The next module introduces the most commonly Nearly all highway agencies use some kind of conventional surface reha- used maintenance treatments for both asphalt-concrete-surfaced and bilitation or maintenance technique (such as seal coats, chip seals, and PCC pavements. Because economic analyses are important in evaluat- thin overlays) to maintain and even extend the service life of their ing the cost-effectiveness of treatments, a module on cost analyses asphalt pavements. The application of these techniques, however, has is included. generally been limited to low-volume roads. On occasion, a state may Peshkin, D. G., K. A. Zimmerman, T. E. Freeman, and K. D. Smith. use a particular surface rehabilitation technique to address specific dis- Pavement Preservation: Preventive Maintenance Treatment, Timing, tress or as a short-term fix on the more heavily travelled routes. The and Selection. Participant Workbook. NHI Course No. 131115. Pub- follow-up evaluation and performance documentation, however, is not lication FHWA-NHI-08-007. National Highway Institute, FHWA, always done. During 1990, several preventive maintenance treatments, U.S. Department of Transportation, 2007. including slurry seals, chip seals, and thin hot-mix overlays, were Pavement Preservation: Preventive Maintenance Treatment, Timing, applied to the existing pavements under the Strategic Highway Research and Selection is a combination and update of two existing pavement Program's specific pavement studies experiment entitled Flexible Pave- preservation courses, NHI Course 131054 on preventive maintenance ment Treatments (SPS-3). The treatments were applied throughout program concepts and implementation, and NHI Course 131058 on the United States and Canada to evaluate the effectiveness of mainte- treatment timing and project selection. The general goal of this course nance strategies on pavement service life. A total of 81 test sites were is to improve the skills of those involved in implementing pavement selected to cover various climates and pavement conditions as well as preservation programs. This includes improving the selection of pave- moderate- to heavy-traffic-volume roads. Besides traditional surface ment preventive maintenance projects and the selection of preventive rehabilitation techniques, many other approaches are now being pur- maintenance treatments. The target audience for this course is mid- or sued, particularly in Europe. These new techniques employ different upper-level highway agency or public works professionals responsible additives or modifiers and aggregate composition as ways to attain for pavement preservation, maintenance, and management, although increased pavement service life. This paper discusses various types of anyone who is involved in the evaluation of pavements for preventive conventional surface rehabilitation techniques, along with many of the maintenance treatments, project selection, or treatment selection will emerging techniques. The discussion includes information on usage,

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103 composition, construction, and (when available) performance and cost. treatment. Factors such as aggregate source and asphalt supplier were This paper complements the work that SHRP has undertaken in this also investigated, but lack of data prevented from reaching any signifi- area. The compilation of such information should assist the designer (or cant conclusion. Based on the relative cost of both treatments and the per- manager) when selecting the type of rehabilitation or maintenance tech- formance observed through this study, it is recommended that Utah nique for higher-volume roads to meet both the system need (budget) Department of Transportation (UDOT) expand the use of CSC to cer- and project performance criteria. tain roads with AADT counts up to 20,000 vpd and continue the existing procedure of using CSC in highway sections with AADTs below 5,000. It Raza, H. State-of-the-Practice Design, Construction, and Performance is also recommended that UDOT modify the existing policies and limit of Micro-Surfacing. Report FHWA-SA-94-051. FHWA, U.S. Depart- the use of OGSC where the running speeds are 55 mph or greater and ment of Transportation, 1994. AADTs are in excess of 25,000 vehicles. Medium-volume facilities (5,000 This document is a comprehensive overview of the terminology, design, to 25,000 AADT) should be sealed with treatments new to UDOT but construction, application, and performance of microsurfacing paving proven in other states. An initial cost analysis showed that the implemen- technology. This technology consists of polymer-modified asphalt emul- tation of the changes suggested as part of this report will result in savings sion, 100% crushed aggregate, mineral filler, water, and field control of over $2 million per year in the maintenance budget, thus allowing for additives as needed. Microsurfacing is primarily used to improve surface better use of resources while still serving the traveling public. friction and to fill wheel ruts. When properly designed and constructed, it has shown good performance for 4 to 7 years. Since microsurfacing is Shatnawi, S., R. Marsh, R. G. Hicks, and H. Zhou. Pavement Preser- applied in a thin layer, 10 to 13 mm, its use should be limited to struc- vation Strategy Selection in California. In Transportation Research turally sound pavements. The one unresolved engineering issue con- Circular E-C098: Maintenance Management 2006, Transportation cerning this technology is the lack of standard mixture design test Research Board of the National Academies, Washington, D.C., 2006, procedures. Although the current testing procedures have resulted pp. 2944. http://onlinepubs.trb.org/onlinepubs/circulars/ec098.pdf. in microsurfacing systems that have generally provided good perfor- The California Department of Transportation (Caltrans) has embarked mance, there is a need to validate and standardize the existing test proce- on an ambitious program for pavement preservation and has estab- dures and adjust design standards to better reflect the effect of various lished a pavement preservation task group (PPTG) to handle activities material combinations. Standardized mixture design procedures and related to this program. One of the subgroups is charged with improv- state acceptance criteria will further enhance the acceptance of this tech- ing the pavement preservation strategy selection process for both asphalt nology by the highway community. and portland cement concrete (PCC) pavements. This paper describes the pavement preservation strategy selection process currently used by Reed, C. M. Seven-Year Performance Evaluation of Single Pass, Thin Caltrans for flexible pavements. It identifies the many factors that are Lift Bituminous Concrete Overlays. Transportation Research Record considered in the process of selecting an appropriate maintenance treat- 1454, TRB, National Research Council, Washington, D.C., 1994. ment for a pavement. These factors include pavement age and condi- In the mid-1980s, the Illinois Department of Transportation (IDOT) tion, traffic levels, expected future plans, as well as available funding and faced the challenge of maintaining an aging highway network at an agency policy. For a properly constructed new pavement, typical pave- acceptable level of service with limited finances. Programming rehabil- ment preservation treatments include those to delay the onset of dis- itation for rural highways was difficult under the existing rehabilitation tresses or to slow down the progress of the distresses. As the pavement policies. To minimize the required maintenance effort on these high- ages, the pavement may become a candidate for routine and contract ways and maximize the available rehabilitation dollars, IDOT initiated maintenance (e.g., crack sealing, grinding, seal coats, or thin hot-mix a single-pass, thin-lift bituminous concrete overlay policy. The new reha- overlays), minor or major rehabilitation, and eventually reconstruction. bilitation strategy, Surface Maintenance at the Right Time (SMART), was Determining the appropriate maintenance treatment, based on the pave- designed for rural highways with low levels of traffic, which otherwise ment condition index of the existing pavement and cost-effectiveness of probably would not be rehabilitated under the current rehabilitation pol- the treatment, also depends on the timing of the treatment. Once a pave- icy. Pavements chosen for rehabilitation under SMART ideally would ment has been identified for pavement maintenance, a specific treatment have age-related distresses, with few indications of structural failure. Proj- is selected to address the specific distress mechanism for the pavement. ect rehabilitation consists of pavement patching, milling, and reflective The most important factors considered when choosing a maintenance crack control treatments where necessary, followed by a 30- to 40-mm treatment include the following: Will the treatment address the dis- (1.25- to 1.50-in.) bituminous concrete overlay. The SMART program tresses present? Can the required preparation for the treatment be car- has been very successful. Performance is high; rehabilitations are expected ried out? Is the treatment cost-effective? Can the treatment be applied to last 7 to 10 years. Through proper project selection and construction, before the situation being addressed changes? A discussion of the basic this program is a cost-effective method for reducing the number of high- steps in the pavement preservation strategy selection process is presented way kilometers needing rehabilitation. in this paper. These steps include the following: (1) assess the existing Romero, P., and D. Anderson. Life Cycle of Pavement Preservation pavement conditions: the pavement distress mechanisms are identified Seal Coats. Report UT-04.07. Utah Department of Transportation, from field pavement surveys along with the use of a field distress identi- Salt Lake City, Utah, 2005. fication manual; (2) determine the feasible treatment options: the feasi- The use of preservation seals on asphalt pavements is a crucial part of bility is determined by a treatments ability to address the functional and any effective pavement management program. It is important to opti- structural condition of the pavement while also meeting any future mize the use of available budgets to extend the life of our pavements as needs; at this stage, the primary purpose of selecting feasible treatments much as possible. The nation's highway system is one of our most valu- is to determine if the identified maintenance treatments work for the able assets. Analysis of the performance of surface treatments on Utah pavement conditions; and (3) analyze and compare the feasible options pavements indicates that open graded surface courses (OGSC) have an with each other: the feasible options are further compared in terms of average life, based on skid resistance, of almost 9 years and that chip seal cost, life expectancy of the treatment, and extended pavement life bene- courses (CSC) have a significantly longer life. Out of all the factors ana- fits due to treatment; to determine cost-effectiveness of each treatment, lyzed, traffic has the most significant effect on the performance of the a life cycle or other cost-effectiveness measure should be made. This

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104 paper also addresses proposed changes to the selection process to design, construction, and selection of cost-effective concrete pavement include treatments for PCC pavements and to include a more detailed preservation strategies. It concentrates primarily on strategies and cost-effectiveness approach using life-cycle cost analysis. methods that are applicable at the project level, and not at the network level, where pavement management activities function and address such Shatnawi, S., and B. D. Toepfer. Pavement Preservation Treatment issues as prioritizing and budgeting. Detailed information is presented Construction Guide. Online Guide. FHWA, U.S. Department of on seven specific concrete pavement preservation treatments: slab sta- Transportation, 2006. http://fhwapap34.fhwa.dot.gov/NHI-PPTCG/ bilization, partial-depth repairs, full-depth repairs, retrofitted edge drains, index1.htm. load transfer restoration, diamond grinding, and joint resealing. In addi- No abstract available. tion, information is provided on pavement evaluation techniques and Shober, S., and D. Friedrichs. Pavement Preservation Strategy. Trans- strategy selection procedures. portation Research Record 1643, TRB, National Research Council, Strategic Highway Research Program (SHRP 2). Project R26: Preser- Washington, D.C., 1998, pp. 4453. vation Approaches for High Traffic Volume Roadways. SHRP 2 An effective pavement management system requires a comprehensive Request for Proposals. 2007. http://onlinepubs.trb.org/onlinepubs/ pavement preservation strategy (PPS). Wisconsin's PPS is guided by a shrp2/R26RFP.pdf. philosophy whose goal is to optimize pavement performance to provide To address the challenges of moving people and goods efficiently and the highest quality service to the customer per unit of expenditure. The safely on the nation's highways, Congress has created the second Strate- PPS is customer oriented and views "service" in terms of user comfort, gic Highway Research Program (SHRP 2). SHRP 2 is a targeted, short- convenience, and safety. The strategy is broad scoped and considers all term research program carried out through competitively awarded pavement management activities, from "do nothing" to reconstruction. contracts to qualified researchers in the academic, private, and public Wisconsin's PPS has program values that are based on solid research sectors. SHRP 2 addresses four strategic focus areas: the role of human that has been field verified. The treatment alternatives recommended behavior in highway safety (Safety); rapid highway renewal (Renewal); for any particular pavement problem address the causes, not the symp- congestion reduction through improved travel time reliability (Relia- toms, of that particular problem--thus, the root cause of the problem bility); and transportation planning that better integrates community, is addressed, and funds are not used to treat merely a symptom. Accord- economic, and environmental considerations into new highway capac- ingly, the PPS is termed a cause-based instead of a schedule-based strat- ity (Capacity). Under current legislative provisions, SHRP 2 will receive egy (applying treatments on a predetermined schedule), or a "worst approximately $170 million, with total program duration of 7 years. first" strategy (treating the worst pavements first). The PPS follows a log- Additional information about SHRP 2 can be found on the program's ical progression through a series of evaluations to convert a set of raw, website at www.TRB.org/SHRP2. field-collected data (ride and distress) to, ultimately, a set of recom- mended actions. The process moves from raw data to an evaluation of United States Army Corps of Engineer (USACE), Naval Facilities the level of the distress. Combinations of distress levels are used to iden- Engineering Command (NAVFAC), and Air Force Civil Engineering tify specific pavement problems. In turn, these pavement problems are Support Agency (AFCESA). Unified Facilities Criteria (UFC): Airfield evaluated as a family to generate appropriate, cost-beneficial solutions. Pavement Condition Survey Procedures Pavements. Publication UFC 3-260-16FA. U.S. Department of Defense, 2004. Shuler, S. Design and Construction of Chip Seals for High Traffic Vol- No abstract available. ume. In Flexible Pavement Rehabilitation and Maintenance (P. S. Kandhal and M. Stroup-Gardiner, eds.), Publication STP 1348, University of Washington Pavement Tools Consortium (PTC). Pave- American Society for Testing and Materials, West Conshohocken, ment Guide Interactive. 2009. http://training.ce.washington.edu/PGI/. This guide is a multimedia CD-ROM whose primary purpose is to pro- Pa., 1998. vide a general pavement overview covering all aspects from materials to No abstract available. design to construction to maintenance. It functions as a "website" that Shuler, S. Evaluation of the Performance, Cost-Effectiveness, and Tim- resides on a CD-ROM and requires only a PC/Mac and minimal freeware ing of Various Preventive Maintenances. Interim Report. Report to access the information. It consists of 275 web pages, 2,500 images, CDOT-DTD-R-2006-6. Colorado Department of Transportation, 50 animations, 14 videos, and 11,000 hyperlinks. Denver, Colo., 2006. Wade, M., R. DeSombre, and D. Peshkin. High Volume/High Speed This research is intended to determine the most economical means of Asphalt Roadway Preventive Maintenance Surface Treatments. Final extending pavement life through preventive maintenance treatments in Report. Report SD99-09. South Dakota Department of Transporta- Colorado. The process proposed to accomplish this includes a survey of tion, Pierre, S.Dak., 2001. current published literature and interviews with individuals responsible The South Dakota Department of Transportation (SDDOT) has made for preventive maintenance, installation of experimental test pavements extensive use of chip seal and sand seal surface treatments in the main- to measure performance under local conditions, and recommendations tenance of their asphalt concrete (AC) pavements. Such surface treat- based on the findings. This report documents the progress made for the ments have been found to provide a cost-effective means of extending first 18 months of a 5-year study. This includes a survey of the literature, the life of AC pavements in South Dakota. Although chip seals and sand interviews with maintenance and construction personnel, the draft of a seals have for the most part been reliable treatments, there have been best practices manual, and the installation of most of the test pavements. some notable failures, especially on high-volume, high-speed roadways. Smith, K. D., T. E. Hoerner, and D. G. Peshkin. Concrete Pavement This project was undertaken to investigate the use of chip seals for such Preservation Workshop: Reference Manual. FHWA, U.S. Department applications and to make recommendations to improve their perfor- of Transportation, 2008. mance. This project also involved the development of guidelines for the This document serves as the reference manual for the 11/2-day FHWA design and construction of chip seals. To evaluate the use of chip seals workshop on concrete pavement preservation. The purpose of the doc- in South Dakota, several efforts were undertaken. First, an extensive lit- ument is to provide the most up-to-date information available on the erature review was conducted to develop an understanding of the latest

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105 practices and experiences. Second, interviews were conducted with Zimmerman, K., and D. Peshkin. The Seven Stallers. In Pavement SDDOT from all departments involved in the chip seal process to inves- Preservation Compendium II, Publication FHWA-IF-06-049, FHWA, tigate their practices and to determine areas for improvement. Finally, U.S. Department of Transportation, 2006, pp. 5964. www.fhwa.dot test sections were constructed to evaluate the performance of standard .gov/pavement/preservation/ppc06.pdf. and modified chip-seal designs. The test sections consisted of 12 chip- This article addresses seven of the most deadly misconceptions about seal designs and included two aggregate types (quartzite and natural pavement preventive maintenance. These misconceptions are deadly aggregate) and alternate chip-seal designs with new gradations and because any one of them is enough to stop a program in its tracks. other modifications and enhancements. Based on these efforts, recom- Therefore, suggestions for addressing each misconception also are pro- mendations are provided to improve chip seal performance. In addi- vided, based on the authors' experiences working with agencies that tion, guidelines were developed to select feasible surface treatments for have been using preventive maintenance concepts for years as well as a specific project. with agencies that are just beginning to implement these programs.