Southeast Transportation Consortium Final Report 515 Asphalt Surface Treatment Practice In Southeastern United States by Hesham Ali, Ph.D., P.E. Mojtaba Mohammadafzali Florida International University Published by: 4101 Gourrier Avenue | Baton Rouge, Louisiana 70808 | (225) 767-9131 | www.ltrc.lsu.edu Asphalt Surface Treatment Practice In Southeastern United States by Hesham Ali, Ph.D., P.E. And Mojtaba Mohammadafzali Florida International University July 2014 Table of Contents SUMMARY CHAPTER 1 INTRODUCTION……………………………………………………………………………….2 PAVEMENT SURFACE TREATMENT ....................................................................................................... 2 SCOPE OF WORK ......................................................................................................................................... 2 METHODOLOGY ......................................................................................................................................... 3 GENERAL SURVEY RESULTS ................................................................................................................... 3 CHAPTER 2 FOG SEALS…………………………………...…………………………………………………6 TECHNIQUE DESCRIPTION ....................................................................................................................... 6 REVIEW OF RECENT WORK ..................................................................................................................... 7 SASHTO STATE OF PRACTICE (SURVEY RESULTS) ............................................................................ 9 CHAPTER 3 REJUVENATION……………………………………………………………..…………………12 TECHNIQUE DESCRIPTION ..................................................................................................................... 12 REVIEW OF RECENT WORK ................................................................................................................... 12 SASHTO STATE OF PRACTICE (SURVEY RESULTS) .......................................................................... 13 CHAPTER 4 CHIP SEAL………………………………...…………………………………………………...14 TECHNIQUE DESCRIPTION ..................................................................................................................... 14 REVIEW OF RECENT WORK ................................................................................................................... 15 SASHTO STATE OF PRACTICE (SURVEY RESULTS) .......................................................................... 19 CHAPTER 5 SANDWICHSEAL AND SCRUB SEAL………………………………………………….…….23 SANDWICH SEAL ...................................................................................................................................... 23 SCRUB SEAL .............................................................................................................................................. 23 REVIEW OF RECENT WORK ................................................................................................................... 24 SASHTO STATE OF PRACTICE (SURVEY RESULTS) .......................................................................... 24 CHAPTER 6 SLURRY SEAL …………………………………………………………………………….25 TECHNIQUE DESCRIPTION ..................................................................................................................... 25 REVIEW OF RECENT WORK ................................................................................................................... 27 SASHTO STATE OF PRACTICE (SURVEY RESULTS) .......................................................................... 28 CHAPTER 7 MICROSURFACING…………………………………………………………………………..29 TECHNIQUE DESCRIPTION ..................................................................................................................... 29 REVIEW OF RECENT WORK ................................................................................................................... 31 SASHTO STATE OF PRACTICE (SURVEY RESULTS) .......................................................................... 31 CHAPTER 8 CAPE SEAL………………………………………………………………………………...…..34 TECHNIQUE DESCRIPTION ..................................................................................................................... 34 REVIEW OF RECENT WORK ................................................................................................................... 34 SASHTO STATE OF PRACTICE (SURVEY RESULTS) .......................................................................... 35 CHAPTER 9 THIN OVERLAYS……...……………………………………………………………………...36 TECHNIQUE DESCRIPTION ..................................................................................................................... 36 REVIEW OF RECENT WORK ................................................................................................................... 37 SASHTO STATE OF PRACTICE (SURVEY RESULTS) .......................................................................... 39 CHAPTER 10 ULTRATHIN BONDED WEARING COURSE………………………………..…………….40 TECHNIQUE DESCRIPTION ..................................................................................................................... 40 REVIEW OF RECENT WORK ................................................................................................................... 42 SASHTO STATE OF PRACTICE (SURVEY RESULTS) .......................................................................... 42 CHAPTER 11 CRACK SEALING AND FILLING…………………………………………………………..44 TECHNIQUE DESCRIPTION ..................................................................................................................... 44 REVIEW OF RECENT WORK ................................................................................................................... 45 SASHTO STATE OF PRACTICE (SURVEY RESULTS) .......................................................................... 46 CHAPTER 12 CONCLUSIONS………………………………………………………………………………47 REFERENCES………………………………………………………………………………………………….49 ACKNOWLEDGEMENT………………………………………………………………………………………53 APPENDIX A: Survey Questionnaires…………………………………………………………………………54 SUMMARY It costs less to maintain roads in good condition than in poor condition. Pavement preservation is a set of activities to extend pavement life, improve safety, and meet road user expectations. Surface treatments are pavement preservation treatments applied to the whole surface of the road. This synthesis summarizes surface treatments’ state of practice in the United States, especially southeastern states. Eleven pavement preservation techniques were addressed: fog seal, rejuvenator seal, chip seal, sandwich seal, scrub seal, slurry seal, microsurfacing, cape seal, thin overlays, ultrathin bonded wearing course and crack sealing/filling. Recent work on surface treatments has been reviewed and summarized. To research surface treatments’ state of practice, a survey was designed and distributed to Southeastern Association of State Highway and Transportation Officials (SASHTO) agencies. Nineteen participants from Florida, Georgia, Louisiana, Virginia, West Virginia, North Carolina, and Arkansas participated in the survey. The electronic survey consisted of three questionnaires asking administrative, technical, and research-related questions. Results showed that thin overlays, crack repairs, microsurfacing, chip seal, and fog seal are the most common preventative maintenance practices. In this report, each chapter is dedicated to one surface treatment technique. Chapters start with a description of the technique, its applications, features, material and equipment requirements, and construction procedures. This is followed by a summary of recent work and implementation status, as obtained from the survey. 1 CHAPTER ONE INTRODUCTION PAVEMENT SURFACE TREATMENT Pavement preservation is an approach to enhance pavement performance using a set of practices that extend the life of the pavement and improve safety and ride quality. According to World Bank’s Pavement Deterioration Model, the cost of bringing back a pavement to good condition if it is left to deteriorate may be four times as the cost of maintaining it in good condition (Shahin, 2005). The results of a UDOT (Utah Department of Transportation) research study showed that it costs less to maintain roads in good condition than in poor condition (Zavitski, et al.). According to the National Cooperative Highway Research Program (NCHRP) Synthesis 223, every dollar spent on preventative maintenance at the correct time in a pavement’s life cycle saves $3-4 in future rehabilitation costs (Geoffroy, 1996). Later work by Galehouse, Moulthrop, & Hicks, (2003) showed that future rehabilitation cost savings are $6–10 for every $1 spent on preventative maintenance, as demonstrated in Figure 1-1. Figure 1-1 Effect of Preventive Maintenance at Life Cycle Cost of the Pavement (Galehouse, Moulthrop, & Hicks, 2003) Some surface treatments are effective for maintaining pavements in good condition. They are applied to the entire surface of the pavement and are usually used for pavements with no major structural deterioration. The relatively low cost and simplicity of these techniques, besides their effectiveness in extending the life of the pavement and improving performance, has attracted many agencies to use them. Chip seal, slurry seal, microsurfacing, surface rejuvenation, fog seal, scrub seal, and thin overlays are among popular surface treatments. SCOPE OF WORK This report is aimed to research asphalt surface treatments’ state of practice in the United