JOINT TRANSPORTATION RESEARCH PROGRAM FHWA/IN/JTRP-2009/12 Final Repor EFFECTIVENESS AND SERVICE LIVES/ SURVIVAL CURVES OF VARIOUS PAVEMENT REHABILITATION TREATMENTS Panagiois Ch. Anasasopoulos Fred L. Mannering John E. Haddock June 2009
INDOT Research TECHNICAL Summary Technology Transfer and Projec Implemenaion Informaion TRB Subjec Code: 24-5 Srucural Rehabiliaion and Overlays June 2009 Publicaion No.: FHWA/IN/JTRP-2009/12, SPR-3228 Final Repor Effeciveness and Service Lives/Survival Curves of Various Pavemen Rehabiliaion Treamens Inroducion Transporaion agencies spend billions of dollars annually on pavemen mainenance and rehabiliaion o mee public, legislaive, and agency expecaions. The effeciveness of various pavemen rehabiliaion reamens in erms of heir impac on he pavemen service life is essenial for cos effecive planning and programming of pavemen mainenance, preservaion and rehabiliaion projecs. Pavemen deerioraion raes, ruck raffic volumes, environmen, geology, and oher facors have significan effecs on he expeced life of he pavemen reamen. Given he role ha pavemen rehabiliaion reamens play in pavemen managemen programs, undersanding he survivabiliy of hese reamens has he poenial o allow improved resource allocaion and more effecive use of Sae funds. The presen research exends he radiional pavemen managemen framework by formulaing mehodologies ha enable he evaluaion of he effeciveness of pavemen rehabiliaion reamens wih respec o reamen service lives and coss. The end produc of his research is a quaniaive ool ha can be used a he projec developmen phase o esimae he effecs of differen ypes of pavemen rehabiliaion reamens for various road funcional classes. The firs objecive of he sudy is o forecas he pavemen rehabiliaion performance in ime. In pracice, pavemen condiion is characerized by a number of poenially inerrelaed performance indicaors. Hence, i is of grea imporance o forecas he pavemen s performance (in erms of all he condiion indicaors ha play an influenial role in he deerminaion of he pavemen s condiion) as a sysem of equaions, by explicily accouning for simulaneous relaionships ha may poenially exis among performance indicaors such as he pavemen surface condiion raing, PCR, (hisorically used by he Indiana Deparmen of Transporaion, INDOT, up o he year 2007), inernaional roughness index (IRI) and ru deph (RUT) measuremens. The second objecive is o approximae he service life of pavemen reamens using saisical models wih a se of pavemen performance hresholds. This ranslaes ino esimaing he service life of each pavemen rehabiliaion reamen for each road funcional class o sudy he elapsed ime unil he pavemen crosses a predeermined hreshold ha is considered criical. The daa used for he pavemen performance saisical modeling were colleced from he INDOT pavemen managemen daabases and from INDIPAVE (a daabase consising of daa on pavemen condiion, weaher, pavemen srucure, raffic, mainenance, and oher informaion a over 10,000 one-mile pavemen secions in he Sae of Indiana). For purposes of performance modeling, values of pavemen performance, raffic loading, weaher effecs and rehabiliaion expendiure were obained from hese daabases. Weaher informaion was also colleced from he Indiana Sae Climae Office. The daa include informaion on 12,250 road secions from 1999 o 2007. The daa were screened for is consisency and accuracy. 24-5 6/09 JTRP-2009/12 INDOT Division of Research Wes Lafayee, IN 47906
Findings The pavemen analysis in his sudy considers various combinaions of pavemen rehabiliaion reamens (wo-course HMA overlay wih or wihou surface milling, concree pavemen resoraion, hree-course HMA overlay wih or wihou surface milling, hree-course HMA overlay wih crack and sea of PCC pavemen and 3-R and 4-R overlay or replacemen reamens). Six road funcional classes (rural and urban of inersaes, non-inersaes of he NHS, and non-inersaes non-nhs) are considered. This allows for esimaion of he performance and service life of he pavemen, corresponding o each reamen and road funcional class. Main findings are summarized below: More han 95 percen of he daa poins of he RUT pavemen performance indicaor were below 0.5 inches indicaing ha his ype of disress has become relaively rare on INDOT highways. Daa poins of he PCR were scaered in a very narrow range (beween a PCR value of 70 and 100) compared o he scaer of he IRI and deflecion. Consequenly, disinc hresholds can be obained from he wide scaer of he IRI and he deflecion. This suggess ha IRI and deflecion are more reliable performance measures han PCR when programming pavemen rehabiliaion reamens. Two-course ho mix asphal, HMA, overlay (wih or wihou surface milling) reamens were found o have a forecased average annual deerioraion in IRI of roughly 6 in/mi. Three-course HMA overlay wih or wihou surface milling reamens were found o have a forecased annual average deerioraion in IRI of abou 5 in/mi. Threecourse HMA overlay wih crack and sea of PCC pavemen reamens were found o have a forecased average annual deerioraion in IRI of roughly 4 in/mi. Pavemen projecs idenified as 3-R and 4-R overlay or replacemen reamens were found o have a forecased average deerioraion in IRI in he range of 4 o 5 in/mi. Concree pavemen resoraion reamens were found o have a forecased average annual deerioraion in IRI of roughly 7 in/mi. Average service life of wo-course HMA overlay (wih or wihou surface milling) was found o be roughly 10 years; 12 years for concree pavemen resoraion; 12 years for hree-course HMA overlay (wih or wihou surface milling); 15 years for hreecourse HMA overlay wih crack and sea of PCC pavemen; and 15 years for 3-R and 4- R overlay or replacemen reamens. These numbers mach closely wih he esimaed service lives in he curren INDOT design manual. Uni cos of pavemen rehabiliaion reamen was srongly correlaed (wih a high degree of saisical confidence) o he service life predicion and consequenly was used in he performance predicion models. Implemenaion Sudy resuls do no warran changes o he INDOT Design Manual. However, a Microsof Excel program was creaed o assis in quanifying he coss per improvemens in pavemen condiion performance measures. INDOT can employ he sofware in generaing esimaed coss ha can be used o assess he effeciveness of various rehabiliaion reamens. This in urn can be used o provide suppor for decisions ha mus weigh he coss wih he available budges so ha he bes decisions can be made. Addiional research is recommended o esablish remaining service life models for pavemen rehabiliaion reamens ha are based on he AASHTO mechanisic empirical pavemen design guide (MEPDG) models. Given he dependen variable will be he remaining service life, he independen variables mus be simple, measureable, readily available (i.e. no sresses and srains) and adapable in he INDOT pavemen managemen sysems. 24-5 6/09 JTRP-2009/12 INDOT Division of Research Wes Lafayee, IN 47906
Summary of he Service Lives of Rehabiliaion Treamens
Conac For more informaion: Prof. Fred L. Mannering Principal Invesigaor School of Civil Engineering Purdue Universiy Wes Lafayee IN 47907 Phone: (765) 496-7913 E-mail: flm@ purdue.edu Prof. John E. Haddock Principal Invesigaor School of Civil Engineering Purdue Universiy Wes Lafayee IN 47907 Phone: (765) 496-3996 E-mail: jhaddock@ purdue.edu Indiana Deparmen of Transporaion Division of Research 1205 Mongomery Sree P.O. Box 2279 Wes Lafayee, IN 47906 Phone: (765) 463-1521 Fax: (765) 497-1665 Purdue Universiy Join Transporaion Research Program School of Civil Engineering Wes Lafayee, IN 47907-1284 Phone: (765) 494-9310 Fax: (765) 496-7996 E-mail: jrp@ecn.purdue.edu hp://www.purdue.edu/jrp 24-5 6/09 JTRP-2009/12 INDOT Division of Research Wes Lafayee, IN 47906
Final Repor FHWA/IN/JTRP-2009/12 Effeciveness and Service Lives/Survival Curves of Various Pavemen Rehabiliaion Treamens by Panagiois Ch. Anasasopoulos Fred L. Mannering and John Haddock Join Transporaion Research Program Projec No. C36-78Q File No. 3-10-16 SPR- 3228 Prepared as a SPR Sudy conduced by he Join Transporaion Research Program Purdue Universiy In cooperaion wih he Indiana Deparmen of Transporaion Federal Highway Adminisraion U.S. Deparmen of Transporaion The conens of his repor reflec he views of he auhors who are responsible for he facs and accuracy of he daa presened herein. The conens do no necessarily reflec he official views or policies of he Indiana Deparmen of Transporaion or he Federal Highway Adminisraion a he ime of publicaion. This repor does no consiue a sandard, specificaion, or regulaion. School of Civil Engineering Purdue Universiy Wes Lafayee, Indiana 47907 June 30, 2009
1. Repor No. 2. Governmen Accession No. 3. Recipien's Caalog No. FHWA/IN/JTRP-2009/12 TECHNICAL REPORT STANDARD TITLE PAGE 4. Tile and Subile Effeciveness and Service Lives/Survival Curves of Various Pavemen Rehabiliaion Treamens 7. Auhor(s) Panagiois Ch. Anasasopoulos, Fred L. Mannering, John E. Haddock 9. Performing Organizaion Name and Address Join Transporaion Research Program 550 Sadium Mall Drive Purdue Universiy Wes Lafayee, IN 47907-2051 5. Repor Dae June 30, 2009 6. Performing Organizaion Code 8. Performing Organizaion Repor No. FHWA/IN/JTRP-2009/12 10. Work Uni No. 11. Conrac or Gran No. SPR-3228 12. Sponsoring Agency Name and Address Indiana Deparmen of Transporaion Sae Office Building 100 Norh Senae Avenue Indianapolis, IN 46204 13. Type of Repor and Period Covered Final Repor 14. Sponsoring Agency Code 15. Supplemenary Noes Prepared in cooperaion wih he Indiana Deparmen of Transporaion and Federal Highway Adminisraion. 16. Absrac The pavemen analysis in his sudy considers various combinaions of pavemen rehabiliaion reamens (wo-course HMA overlay wih or wihou surface milling, concree pavemen resoraion, hree-course HMA overlay wih or wihou surface milling, hree-course HMA overlay wih crack and sea of PCC pavemen and 3-R and 4-R overlay or replacemen reamens). Six road funcional classes (rural and urban of inersaes, non-inersaes of he NHS, and non-inersaes non-nhs) are considered. This allows for esimaion of he performance and service life of he pavemen, corresponding o each reamen and road funcional class. Main findings; More han 95 percen of he daa poins of he RUT pavemen performance indicaor were below 0.5 inches indicaing ha his ype of disress has become relaively rare on INDOT highways. Daa poins of he PCR were scaered in a very narrow range (beween a PCR value of 70 and 100) compared o he scaer of he IRI and deflecion. Consequenly, disinc hresholds can be obained from he wide scaer of he IRI and he deflecion. This suggess ha IRI and deflecion are more reliable performance measures han PCR when programming pavemen rehabiliaion reamens. Two-course ho mix asphal, HMA, overlay (wih or wihou surface milling) reamens were found o have a forecased average annual deerioraion in IRI of roughly 6 in/mi. Three-course HMA overlay wih or wihou surface milling reamens were found o have a forecased annual average deerioraion in IRI of abou 5 in/mi. Three-course HMA overlay wih crack and sea of PCC pavemen reamens were found o have a forecased average annual deerioraion in IRI of roughly 4 in/mi. Pavemen projecs idenified as 3-R and 4-R overlay or replacemen reamens were found o have a forecased average deerioraion in IRI in he range of 4 o 5 in/mi. Concree pavemen resoraion reamens were found o have a forecased average annual deerioraion in IRI of roughly 7 in/mi. Average service life of wo-course HMA overlay (wih or wihou surface milling) was found o be roughly 10 years; 12 years for concree pavemen resoraion; 12 years for hree-course HMA overlay (wih or wihou surface milling); 15 years for hreecourse HMA overlay wih crack and sea of PCC pavemen; and 15 years for 3-R and 4-R overlay or replacemen reamens. These numbers mach closely wih he esimaed service lives in he curren INDOT design manual. Uni cos of pavemen rehabiliaion reamen was srongly correlaed (wih a high degree of saisical confidence) o he service life predicion and consequenly was used in he performance predicion models. 17. Key Words Remaining Service Life, Pavemen Rehabiliaion, 18. Disribuion Saemen No resricions. This documen is available o he public hrough he Naional Technical Informaion Service, Springfield, VA 22161 19. Securiy Classif. (of his repor) 20. Securiy Classif. (of his page) 21. No. of Pages 22. Price Unclassified Unclassified 237 Form DOT F 1700.7 (8-69)
ii ACKNOWLEDGMENTS The compleion of his sudy would no have been compleed wihou he help and suppor from many people. The auhors would like o hank Dr. Samuel Labi, Olson Disinguished Professor Kumares C. Sinha, Professor Andrew P. Tarko, and Dr. Bob G. McCullouch, for heir help and conribuion hroughou his research. Their inpu in his work is highly appreciaed. Special hanks go o Bill Flora (Indiana Deparmen of Transporaion) for his help in collecing pavemen daa.
iii TABLE OF CONTENTS Page LIST OF TABLES...v LIST OF FIGURES... viii ABSTRACT... xii CHAPTER 1. INTRODUCTION...1 1.1. Background and Problem Saemen... 1 1.2. Research Objecives... 3 1.3. Research Scope... 4 1.4. Organizaion... 5 CHAPTER 2. LITERATURE REVIEW...7 2.1. Inroducion... 7 2.2. Conceps and Definiions... 7 2.3. Types of Pavemen Disress... 9 2.4. Pavemen Treamens... 11 2.4.1. Flexible Pavemens... 14 2.4.2. Rigid Pavemens... 18 2.4.3. Asphal Concree on Porland Cemen Concree Pavemens Mainenance... 21 2.5. Pavemen Performance Modeling... 21 2.5.1. Shor Term Pavemen Performance Modeling... 21 2.5.2. Long Term Pavemen Performance Modeling... 27 2.5.3. Review of Pas Work in Pavemen Performance Modeling... 32 2.5.4. Pavemen Condiion Indicaors... 34 2.5.5. Pavemen Performance Thresholds... 35 2.6. Evaluaing Cos Effeciveness of Pavemen Treamens... 42 2.6.1. Maximum Benefi Approach... 43 2.6.2. Leas (Life-Cycle) Cos Approach... 44 2.6.3. Combinaion of Maximum Benefi and Life-Cycle Cos Approaches... 46 2.7. Decision Crieria for Mainenance, Rehabiliaion and Reconsrucion... 46 2.8. Mainenance, Rehabiliaion and Reconsrucion: Ranking and Opimizaion... 54 2.9. Key Findings from he Lieraure Review... 58
iv CHAPTER 3. METHODOLOGICAL FRAMEWORK AND DATA...60 3.1. Overview of he Sudy Approach... 60 3.2. Analysis Seps... 62 3.3. Daa: Sources and Descripion... 65 3.4. Summary Saisics... 66 CHAPTER 4. PAVEMENT PERFORMANCE MODELING...75 4.1. Inroducion... 75 4.2. Mehodology... 75 4.2.1. Overview of he Economeric Modeling Approach... 85 4.2.2. Descripive Saisics... 91 4.3. Pavemen Performance Model Resuls... 107 4.3.1. Rural Roads: Inersaes... 109 4.3.2. Rural Roads: Non-Inersaes NHS... 109 4.3.3. Rural Roads: Non-Inersaes Non-NHS... 116 4.3.4. Urban Roads: Inersaes... 122 4.3.5. Urban Roads: Non-Inersaes NHS... 128 4.3.6. Urban Roads: Non-Inersaes Non-NHS... 134 4.4. Discussion of he Model Resuls... 146 4.5. Pavemen Performance Forecasing... 149 4.5.1. Rural Inersae Models: Pavemen Condiion Forecasing... 152 4.5.2. Rural Non-Inersae of he NHS Models: Forecasing he Pavemen Condiion... 156 4.5.3. Rural Non-Inersae Non-NHS Models: Forecasing he Pavemen Condiion... 160 4.5.4. Urban Inersae Models: Forecasing he Pavemen Condiion... 164 4.5.5. Urban Non-Inersae of he NHS Models: Forecasing he Pavemen Condiion... 168 4.5.6. Urban Non-Inersae Non-NHS Models: Forecasing he Pavemen Condiion... 172 4.5.7. Forecasing Accuracy of he Models... 176 4.6. Service Lives of Pavemen Rehabiliaion Treamens... 178 4.6.1. Graphical Approximaion of he Asse Service Life... 179 CHAPTER 5. CONCLUSIONS...196 5.1. Conribuion of his Research... 196 5.2. Discussion of Research Resuls and Lessons Learned... 197 5.3. Direcions for Fuure Research... 200 LIST OF ABBREVIATIONS...202 LIST OF REFERENCES...206
v LIST OF TABLES Table Page 2.1 Composie/flexible and joined concree pavemens disresses...11 2.2 Typical reamens in various caegories of pavemen reamen aciviies (Source: Labi and Sinha, 2003a)...12 2.3 Federal pavemen roughness hresholds for inersae faciliies (Source: FHWA, 1999)...36 2.4 Temporal rends in rigger values (mean values from Lampey e al., 2005)...37 2.5 Hisorical rigger values (mean values from Lampey e al., 2005)...38 2.6 Pavemen hresholds (Source: Shober and Friedrichs, 1998)...39 2.7 Decision for mainenance reamens on inersae and primary highways from Monana DOT PMS (Source: Hicks e al., 2000)...40 2.8 Skid number hresholds for rehabiliaion (Source: Ksaibai, e al., 1996)...41 2.9 Expeced life-span of rehabiliaion alernaives for asphal pavemens (Source: Uddin e al., 1987)...50 2.10 Daa reference in a ypical caalogue for an asphal srucural overlay of 100 mm hickness (Source: Flinsch e al., 1994)...50 2.11 Prevenive mainenance effeciveness on pavemen condiion (Source: Labi and Sinha, 2003a)...51 2.12 Prevenive mainenance effeciveness on pavemen condiion (Source: Labi and Sinha, 2003a)...53 2.13 Prevenive mainenance effeciveness on pavemen condiion (Source: Labi and Sinha, 2003a)...54 3.1 Abbreviaions of seleced variables...67 3.2 Summary saisics of seleced variables: rural inersaes...68 3.3 Summary saisics of seleced variables: rural non-inersaes of he NHS...69 3.4 Summary saisics of seleced variables: rural non-inersaes non-nhs...70 3.5 Summary saisics of seleced variables: urban inersaes...71 3.6 Summary saisics of seleced variables: urban non-inersaes of he NHS...72 3.7 Summary saisics of seleced variables: urban non-inersaes non-nhs...73 4.1 Correlaion coefficiens for he pavemen condiion indicaors (righ afer rehabiliaion has occurred)...80 4.2 Decision rule for selecion of he appropriae sysem equaions mehod...87 4.3 Abbreviaions of variables relaed o he pavemen condiion...92 4.4 Two-course HMA overlay wih or wihou surface milling SURE...110 4.5 Concree pavemen resoraion SURE...111 4.6 Three-course HMA overlay wih or wihou surface milling SURE...112
vi Table Page 4.7 Three-course HMA overlay wih crack and sea of PCC pavemen SURE...113 4.8 3-R and 4-R overlay reamens SURE...114 4.9 3-R/4-R pavemen replacemen reamens SURE...115 4.10 Two-course HMA overlay wih or wihou surface milling SURE...116 4.11 Concree pavemen resoraion SURE...117 4.12 Three-course HMA overlay wih or wihou surface milling SURE...118 4.13 Three-course HMA overlay wih crack and sea of PCC pavemen SURE...119 4.14 3-R and 4-R overlay reamens SURE...120 4.15 3-R/4-R pavemen replacemen reamens SURE...121 4.16 Two-course HMA overlay wih or wihou surface milling SURE...122 4.17 Concree pavemen resoraion SURE...123 4.18 Three-course HMA overlay wih or wihou surface milling SURE...124 4.19 Three-course HMA overlay wih crack and sea of PCC pavemen SURE...125 4.20 3-R and 4-R overlay reamens SURE...126 4.21 3-R/4-R pavemen replacemen reamens SURE...127 4.22 Two-course HMA overlay wih or wihou surface milling SURE...128 4.23 Concree pavemen resoraion SURE...129 4.24 Three-course HMA overlay wih or wihou surface milling SURE...130 4.25 Three-course HMA overlay wih crack and sea of PCC pavemen SURE...131 4.26 3-R and 4-R overlay reamens SURE...132 4.27 3-R/4-R pavemen replacemen reamens SURE...133 4.28 Two-course HMA overlay wih or wihou surface milling SURE...134 4.29 Concree pavemen resoraion SURE...135 4.30 Three-course HMA overlay wih or wihou surface milling SURE...136 4.31 Three-course HMA overlay wih crack and sea of PCC pavemen SURE...137 4.32 3-R and 4-R overlay reamens SURE...138 4.33 3-R/4-R pavemen replacemen reamens SURE...139 4.34 Two-course HMA overlay wih or wihou surface milling SURE...140 4.35 Concree pavemen resoraion SURE...141 4.36 Three-course HMA overlay wih or wihou surface milling SURE...142 4.37 Three-course HMA overlay wih crack and sea of PCC pavemen SURE...143 4.38 3-R and 4-R overlay reamens SURE...144 4.39 3-R/4-R pavemen replacemen reamens SURE...145 4.40 Acual forecas values of he pavemen condiion for he rural inersaes models...156 4.41 Acual forecas values of he pavemen condiion for he rural non-inersaes of he NHS models...160 4.42 Acual forecas values of he pavemen condiion for he rural non-inersaes non- NHS models...164 4.43 Acual forecas values of he pavemen condiion for he urban inersaes models...168 4.44 Acual forecas values of he pavemen condiion for he urban non-inersaes of he NHS models...172
vii Table Page 4.45 Acual forecas values of he pavemen condiion for he urban non-inersaes non- NHS models...176 4.46 MAPE values for all rehabiliaion reamens by road funcional class...177 4.47 Pavemen condiion hresholds by road funcional class (Source: Anasasopoulos, 2009)...179 4.48 Graphical approximaion of he service life of he reamens...195
viii LIST OF FIGURES Figure Page 2.1 Pavemen preservaion pracices...9 2.2 Pavemen preservaion pracices (Source: Labi and Sinha, 2003a)...13 2.3 Typical correcive mainenance reamen ypes in Indiana (Source: Labi and Sinha, 2003a)...13 2.4 Typical prevenive mainenance reamen ypes in Indiana (Source: Labi and Sinha, 2003a)...14 2.5 Measuring shor-erm effeciveness: Deerioraion reducion concep (Source: Labi and Sinha, 2003a)...23 2.6 Concepual illusraion of deerioraion reducion rae (Labi and Sinha, 2004)...26 3.1 General mehodological framework...63 4.1 Pavemen performance modeling wih performance indicaors (PI)...77 4.2 Relaionship beween IRI and PCR...80 4.3 Relaionship beween IRI and ru deph...81 4.4 Relaionship beween IRI and FWD...81 4.5 Relaionship beween PCR and ru deph...82 4.6 Relaionship beween PCR and FWD...82 4.7 Relaionship beween ru deph and FWD...83 4.8 Descripion of he analysis segmenaion...84 4.9 Mean IRI in rural inersaes for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...93 4.10 Mean PCR in rural inersaes for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...93 4.11 Mean ru deph in rural inersaes for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...94 4.12 Mean deflecion in rural inersaes for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...94
ix Figure Page 4.13 Mean IRI in rural non-inersaes of he NHS for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...95 4.14 Mean PCR in rural non-inersaes of he NHS for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...95 4.15 Mean ru deph in rural non-inersaes of he NHS for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...96 4.16 Mean deflecion in rural non-inersaes of he NHS for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...96 4.17 Mean IRI in rural non-inersaes non-nhs for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...97 4.18 Mean PCR in rural non-inersaes non-nhs for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...97 4.19 Mean ru deph in rural non-inersaes non-nhs for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...98 4.20 Mean deflecion in rural non-inersaes non-nhs for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...98 4.21 Mean IRI in urban inersaes for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...99 4.22 Mean PCR in urban inersaes for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...99 4.23 Mean ru deph in urban inersaes for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...100 4.24 Mean deflecion in urban inersaes for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...100 4.25 Mean IRI in urban non-inersaes of he NHS for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...101 4.26 Mean PCR in urban non-inersaes of he NHS for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...101 4.27 Mean ru deph in urban non-inersaes of he NHS for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...102 4.28 Mean deflecion in urban non-inersaes of he NHS for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...102 4.29 Mean IRI in urban non-inersaes non-nhs for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...103 4.30 Mean PCR in urban non-inersaes non-nhs for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...103
x Figure Page 4.31 Mean ru deph in urban non-inersaes non-nhs for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...104 4.32 Mean deflecion in urban non-inersaes non-nhs for he base year (year 1) and he hree consecuive years (years 2, 3, and 4) for each rehabiliaion reamen...104 4.33 Represenaion of he sudy period deerminaion for each observaion...108 4.34 IRI forecass by reamen ype for rural inersaes...154 4.35 PCR forecass by reamen ype for rural inersaes...154 4.36 RUT forecass by reamen ype for rural inersaes...155 4.37 FWD forecass by reamen ype for rural inersaes...155 4.38 IRI forecass by reamen ype for rural non-inersaes of he NHS...158 4.39 PCR forecass by reamen ype for rural non-inersaes of he NHS...158 4.40 RUT forecass by reamen ype for rural non-inersaes of he NHS...159 4.41 FWD forecass by reamen ype for rural non-inersaes of he NHS...159 4.42 IRI forecass by reamen ype for rural non-inersaes non-nhs...162 4.43 PCR forecass by reamen ype for rural non-inersaes non-nhs...162 4.44 RUT forecass by reamen ype for rural non-inersaes non-nhs...163 4.45 FWD forecass by reamen ype for rural non-inersaes non-nhs...163 4.46 IRI forecass by reamen ype for urban inersaes...166 4.47 PCR forecass by reamen ype for urban inersaes...166 4.48 RUT forecass by reamen ype for urban inersaes...167 4.49 FWD forecass by reamen ype for urban inersaes...167 4.50 IRI forecass by reamen ype for urban non-inersaes of he NHS...170 4.51 PCR forecass by reamen ype for urban non-inersaes of he NHS...170 4.52 RUT forecass by reamen ype for urban non-inersaes of he NHS...171 4.53 FWD forecass by reamen ype for urban non-inersaes of he NHS...171 4.54 IRI forecass by reamen ype for urban non-inersaes non-nhs...174 4.55 PCR forecass by reamen ype for urban non-inersaes non-nhs...174 4.56 RUT forecass by reamen ype for urban non-inersaes non-nhs...175 4.57 FWD forecass by reamen ype for urban non-inersaes non-nhs...175 4.58 MAPE disribuion...177
xi Figure Page 4.59 Graphical approximaion of he pavemen service life and remaining service life...180 4.60 IRI forecass and hresholds for rural inersaes...183 4.61 PCR forecass and hresholds for rural inersaes...183 4.62 RUT forecass and hresholds for rural inersaes...184 4.63 FWD forecass and hresholds for rural inersaes...184 4.64 IRI forecass and hresholds for rural non-inersaes of he NHS...185 4.65 PCR forecass and hresholds for rural non-inersaes of he NHS...185 4.66 RUT forecass and hresholds for rural non-inersaes of he NHS...186 4.67 FWD forecass and hresholds for rural non-inersaes of he NHS...186 4.68 IRI forecass and hresholds for rural non-inersaes non-nhs...187 4.69 PCR forecass and hresholds for rural non-inersaes non-nhs...187 4.70 RUT forecass and hresholds for rural non-inersaes non-nhs...188 4.71 FWD forecass and hresholds for rural non-inersaes non-nhs...188 4.72 IRI forecass and hresholds for urban inersaes...189 4.73 PCR forecass and hresholds for urban inersaes...189 4.74 RUT forecass and hresholds for urban inersaes...190 4.75 FWD forecass and hresholds for urban inersaes...190 4.76 IRI forecass and hresholds for urban non-inersaes of he NHS...191 4.77 PCR forecass and hresholds for urban non-inersaes of he NHS...191 4.78 RUT forecass and hresholds for urban non-inersaes of he NHS...192 4.79 FWD forecass and hresholds for urban non-inersaes of he NHS...192 4.80 IRI forecass and hresholds for urban non-inersaes non-nhs...193 4.81 PCR forecass and hresholds for urban non-inersaes non-nhs...193 4.82 RUT forecass and hresholds for urban non-inersaes non-nhs...194 4.83 FWD forecass and hresholds for urban non-inersaes non-nhs...194
xii ABSTRACT Transporaion agencies spend billions of dollars annually on pavemen mainenance and rehabiliaion o mee public, legislaive, and agency expecaions. However, he effeciveness of various pavemen rehabiliaion reamens in erms of heir effec on he pavemen service life is no well undersood. This is furher complicaed by he effec ha physical deerioraion, load volumes, weaher, geology, and oher facors may have on he effeciveness of he reamen. Given he role ha pavemen rehabiliaion reamens play in he pavemen-managemen program, undersanding he survivabiliy of hese reamens has he poenial o provide improved resource allocaion and more effecive use of Sae funds. The presen research exends he radiional pavemen-managemen framework by formulaing mehodologies ha enable ransporaion agencies o evaluae he effeciveness of heir pavemen rehabiliaion reamens wih respec o each reamen service life. The end produc of his research is a quaniaive ool ha can be used a he projec developmen phase o esimae he effecs of differen ypes of pavemen rehabiliaion reamens for various road funcional classes. The models developed in his sudy are esimaed using daa from he Indiana Deparmen of Transporaion. The pavemen performance is forecased and influenial facors ha affec performance deerioraion are idenified. A sysem of equaions approach is inroduced, o explicily accoun for simulaneous relaionships ha poenially exis among pavemen performance indicaors. To approximae he service life of he pavemen rehabiliaion reamens a se of pavemen-performance hresholds are uilized.
xiii A major conribuion of his work is he demonsraion of a general approach ha can be applied for comprehensive analysis of he effecs of pavemen reamens, while aking ino accoun specific characerisics of he infrasrucure sysem. The resuls se forh herein provide a beer undersanding of he inerrelaionships among pavemen rehabiliaion reamen, pavemen condiion, road funcional class, pavemen service life, raffic loads and rucks, weaher and soil condiion, and rehabiliaion expendiure. Moreover, his sudy illusraes he seps necessary o evaluae he pavemen-reamen effeciveness and demonsraes how analysis can be carried ou and ulimaely improved. Given he complexiy of he problem and he limiaions of available daa, his sudy should be viewed as an incremenal sep oward enabling ransporaion agencies o make beer decisions regarding a number of pavemen rehabiliaion reamens, allowing he selecion of reamen opions ha will las he longes given funding limiaions.
1 CHAPTER 1. INTRODUCTION 1.1. Background and Problem Saemen Transporaion Agencies spend billions of dollars annually on managing a wide range of asses o mee public, legislaive, and agency expecaions. These asses vary from he physical ransporaion infrasrucure, such as roadways, srucures, and heir associaed feaures, o equipmen, maerial socks, daa and informaion, and human resources. Asse managemen can be associaed wih nearly every aspec of ransporaion agencies work, including design, planning, engineering, finance, and programming. Wih regard o he problem of pavemen reamens, he effeciveness of various reamens in erms of heir effec on pavemen life is no ha well undersood. The issue is complicaed furher by he effec ha physical deerioraion, load volumes, weaher and soil condiions, locaion (space) and oher facors may have on he effeciveness of he reamen. Given he imporan role ha pavemen reamens play, undersanding he survivabiliy of hese reamens has he poenial o provide improved resource allocaion and more effecive use of Sae funds. Pavemen mainenance and rehabiliaion is one of he mos criical and cosly forms of infrasrucure asse managemen. Preserving pavemens in an appropriae manner, exends heir service life, and mos imporanly improves mooriss safey and saisfacion and saves public ax dollars. Keenan (2005) defines pavemen preservaion as a sysem where pavemen reamen occurs a an opimum ime wih he goal of maximizing pavemen service life.
2 Anoher erm ypically used for pavemen preservaion is prevenive mainenance which seeks o rea pavemens before disress has reached a level where he srucural inegriy of he pavemen is compromised. The acions required o resore pavemens o a level where prevenive mainenance can be applied, is defined as correcive mainenance. Pavemens lef o deeriorae wihou imely mainenance reamens are more likely o require major rehabiliaion and reconsrucion. Typically, pavemens perform well unil a poin in heir service life where heir performance rapidly deerioraes o failure. I has been shown ha invesing in pavemen preservaion before ha deerioraion poin significanly reduces fuure rehabiliaion and/or reconsrucion coss (Keenan, 2005), providing highway agencies wih feasible alernaives in addressing pavemen needs where pavemen condiion is improved and service life exended. Therefore, preserving pavemens while opimizing he efficiency of invesmens, can improve he highway sysem and road-user saisfacion. Typically, pavemen preservaion is conduced before he pavemen s srucure fails. In some cases, however, he reamen may no be relevan o he pavemen s condiion and he pavemen may be reaed long before or even long afer is condiion requires i. Hence, forecasing pavemen condiions is very imporan because i allows for a reliable esimaion of he pavemen service life from he implemenaion of a specific reamen. Good models for performance forecasing have always been challenging (Darer 1980), due o he need o predic he pavemen s performance and condiion so as o deermine opimal imes o perform preservaion aciviies, and predic heir impacs on pavemen condiion and remaining service life. The serviceabiliy-performance concep plays an imporan role in pavemen managemen. The effeciveness of a preservaion reamen (also referred o as deerioraion reducion) is indicaed as he increase in posiive service aribues (or reducion in negaive aribues) of he pavemen sysem. In pavemen mainenance and rehabiliaion, such effeciveness ypically indicaes an improvemen of he surface condiion (e.g., pavemen condiion raing (PCR), ruing deph, pavemen qualiy index
3 (PQI), surface deflecion, presen serviceabiliy index (PSI), ec.) or a deerioraion of he surface roughness (e.g., inernaional roughness index (IRI), roughness number (RN), ec. (Anasasopoulos, 2009a). Given he size of he pavemen managemen budge and he imporance of pavemen preservaion in he susainabiliy of ransporaion infrasrucure, an improved undersanding of he effeciveness of various preservaion reamens could ulimaely save millions of dollars by allowing for more efficien allocaion of resources. The findings of he presen research sudy will enable beer decisions regarding a number of pavemen rehabiliaion reamens, allowing he selecion of pavemen reamen opions ha will las he longes given he iniial pavemen s condiions, weaher and soil condiions, load volumes and ohers facors ha may be found o significanly affec he survivabiliy of he various pavemen-reamen opions. 1.2. Research Objecives The main objecive of his research is o idenify a comprehensive mehodological framework ha can be used o evaluae he effeciveness of pavemen reamens wih respec o each reamen s service life. To his end, various pavemen rehabiliaion reamens are evaluaed for heir effeciveness wih regard o pavemen life for various road funcional classes. There are wo specific objecives. The firs one is o forecas he pavemen performance over ime. Tha is, o invesigae how pavemen condiion deerioraes over ime, and idenify he influenial facors ha affec his deerioraion. In pracice, pavemen condiion is characerized by a number of performance indicaors. Each indicaor may have no relaionship wih he oher indicaors, or may be somehow simulaneously relaed o hem. In all cases, however, here is a correlaion beween poor pavemen condiion and poor performance indicaors. Hence, i is of grea imporance o forecas he pavemen s performance (in erms of all he condiion indicaors ha play an
4 influenial role in he deerminaion of he pavemen s condiion) as a sysem of equaions, by explicily accouning for simulaneous relaionships ha may exis among hem. The second objecive is o approximae he service life of pavemen reamens using a pavemen performance analysis and a se of pavemen performance hresholds. This ranslaes ino esimaing he service life of each pavemen rehabiliaion reamen for each road funcional class o sudy he elapsed ime unil he pavemen crosses a predeermined hreshold ha is considered criical. 1.3. Research Scope The scope of he presen sudy is defined o address he problem saemen in a comprehensive manner, while mainaining a realisic approach based on daa availabiliy. Various aspecs of he sudy scope are: Coverage: The mehodological framework focuses on six pavemen rehabiliaion reamens in he Sae of Indiana; wo-course ho-mix asphal (HMA) overlay wih or wihou surface milling, concree pavemen resoraion, hree-course HMA overlay wih or wihou surface milling, hree-course HMA overlay wih crack and sea of Porland cemen concree (PCC) pavemen, 3-R (resurfacing, resoraion and rehabiliaion) and 4-R (resurfacing, resoraion, rehabiliaion and reconsrucion) overlay reamens, and 3-R/4-R pavemen replacemen reamens. The firs wo are funcional reamens (which are relaed o he surface or profile characerisics and heir ineracions wih vehicles), whereas he res are srucural (which are relaed o he pavemen s abiliy o carry loads) (Labi and Sinha, 2003a). Because he effec of each reamen is expeced o be differen among roads ha serve differen purposes, and he crieria used o se he serviceabiliy hreshold(s) differ based on he funcional class of he road, he analysis is conduced a a road funcional-class level. As such, he analysis is
5 performed separaely for rural and urban inersaes, non-inersaes of he Naional Highway Sysem (NHS), and non-inersaes ha do no belong o he NHS. As pavemen condiion indicaors, he inernaional roughness index (IRI), pavemen condiion raing (PCR), ru deph, and surface deflecion (which can be used only for he srucural reamens) are uilized. Analysis Period: A nine (9) year sudy period saring from 1999 o 2007, is seleced. For he purpose of he sudy, only road secions wih available hisorical rehabiliaion daa are considered in he analysis (road secions rehabiliaed in 1999 or afer). This decision is based on he need of esablishing raional comparison crieria and he availabiliy of pavemen condiion, rehabiliaion cos, road secion lengh, raffic loads, weaher and soil informaion, ec. However, informaion for many oher road secions is reviewed o gain insighs relaing o he saus of various rehabiliaion reamens used in he Sae of Indiana. 1.4. Organizaion This repor sars wih a general descripion of he mehodological framework, followed by a comprehensive lieraure review which seeks o undersand mehodological approaches and findings of pas research effors. The main research objecive is o formulae a mehodological framework ha can be used o sudy he relaionship beween differen pavemen rehabiliaion reamens, pavemen aribues, as well as emporal and spaial aribues, for pavemen rehabiliaion reamen projecs in Indiana. The analysis involves he deerminaion of he pavemen performance indicaors and subsequen forecasing of pavemen performance (by accouning for poenial simulaneous relaionships among he indicaors). Also, using pavemen performance hresholds from he lieraure, he analysis provides an approximaion of he pavemen reamen service life and deerminaion of imporan influenial facors ha
6 significanly affec i. The final sep of his research sudy involves he documenaion of he resuls and conclusions.
7 CHAPTER 2. LITERATURE REVIEW 2.1. Inroducion Pavemen managemen has become increasingly complex over he years due o significan raffic/populaion growh and limied resources. In view of his, in 1998, he American Associaion of Sae Highway and Transporaion Officials (AASHTO) recognized he imporance of infrasrucure managemen for ransporaion agencies, and adoped i as a prioriy sraegic iniiaive. Infrasrucure managemen can be associaed wih nearly any planning, engineering, finance, programming, consrucion, mainenance, and informaion sysems aciviy, conduced by a ransporaion agency. However, pavemens presen ransporaion agencies wih heir mos challenging managemen problem. Transporaion agencies spend a very large porion of heir budges on pavemen preservaion and hey coninually seek o enhance oversigh mechanisms no only o ensure ha hese invesmens are yielding heir worh bu also o ascerain he impac of changing funding levels on pavemen performance. Proper pavemen managemen can save money for ransporaion agencies, and improve he safey and saisfacion of he mooriss. 2.2. Conceps and Definiions Pavemen managemen can be defined as a sysemaic process of cos-effecively mainaining, upgrading and operaing pavemens (FHWA, 1999). The scope of pavemen managemen can be summarized in he following hree seps (Galehouse e al., 2003); consideraion of various invesmen sraegies, provision of a raional decision process, and overall condiion of he pavemen sysem improvemen a a lower cos.
8 Prevenive mainenance is a planned sraegy of cos-effecive reamens o an exising roadway sysem ha preserves he sysem, and delays fuure deerioraion. As a ool for pavemen preservaion, prevenive mainenance is associaed wih he on-ime applicaion of he appropriae non-srucural reamens o differen pavemen ypes. Pavemen preservaion ypically includes correcive and prevenive mainenance and someimes minor rehabiliaion projecs. However, i may also include all he aciviies underaken o provide and mainain serviceable roadways. New or reconsruced pavemens, and pavemens requiring major rehabiliaion or reconsrucion, are usually excluded. Wih pavemen preservaion invesmens in he highway sysem, pavemen life is exended, pavemen performance is improved, cos effeciveness is enhanced, and end users needs are me. Figure 2.1 illusraes a depicion on he pavemen preservaion vs. rehabiliaion conceps. Reacive mainenance ypically includes unscheduled aciviies ha respond o siuaions ha are beyond he agency s conrol (e.g., pohole paching, ru filling, ec.). Emergency mainenance includes aciviies under exreme condiions when life and propery are a risk (e.g., rockslides, earh slides, washous, rigid pavemen blowups, ec.).
9 Pavemen Condiion Prevenive Threshold Rehabiliaion Threshold Time Figure 2.1 Pavemen preservaion pracices 2.3. Types of Pavemen Disress There are differen guidelines in deermining he severiy of pavemen disress. Miller and Bellinger (2003) provide guidelines o idenify he disress and he assessmen of he level of severiy. For flexible pavemens, including asphal overlays on asphal or concree pavemens, disresses can be classified ino: cracking (block cracking, edge cracking, faigue cracking, wheel and non-wheel pah longiudinal cracking, ransverse cracking, and reflecion cracking a joins), paching and poholes (pach, pach deerioraion, and poholes), surface deformaion (ruing and shoving), surface defecs (bleeding, raveling, and polished aggregae), and miscellaneous disress (lane-o-shoulder drop-off, and waer bleeding and pumping). For joined and reinforced Porland cemen concree (PCC) pavemens, including concree overlays on PCC pavemens, disresses can be classified ino: cracking (longiudinal cracking, ransverse cracking, corner break, and durabiliy cracking),
10 join deficiencies (ransverse and longiudinal join seal damage, and spalling of longiudinal joins and of ransverse joins), surface defecs (map cracking, scaling, pop-ous, and polished aggregae), pach/ pach deerioraion (waer bleeding and pumping), and miscellaneous disress (fauling of ransverse joins and cracks, lane-o-shoulder drop-off and separaion, and blowups). For coninuously reinforced concree pavemens (CRCP), disresses can be caegorized ino: cracking (ransverse cracking, longiudinal cracking, and durabiliy cracking), surface disress (pop-ous, scaling, map cracking, and polished aggregae), and miscellaneous disress (lane-o-shoulder drop-off and separaion, spalling of longiudinal joins, waer bleeding and pumping, longiudinal join seal damage, blowups, ransverse consrucion join deerioraion, pach/pach deerioraion, punchous). In addiion, he Indiana Deparmen of Transporaion (INDOT, 1998) developed he Pavemen Condiion Daa Collecion Manual where surface disresses are classified for flexible/composie pavemens and joined concree pavemens 1, as shown in Table 2.1. On he oher hand, he INDOT Design Manual (INDOT, 2008) provides anoher inerpreaion of disress classificaion: Flexible (asphal) pavemen: block cracking, ruing, shoulder drop-off, hermal cracking, alligaor/faigue cracking, weahering, sripping, flushing, fros heave, longiudinal cracking, polishing, raveling, and reflecive cracking; Rigid (concree) pavemen: blow-ups, polishing, poor ride-abiliy, join seal failure, alkali-silica reaciviy, srucural failure, pop-ous, corner breaks, 1 Noe ha in his case, he surface deformaions (i.e., ruing and shoving) and pavemen roughness are evaluaed separaely from he pavemen surface condiion raing.
11 durabiliy cracking, longiudinal cracking, punch-ous, ransverse cracking, scaling, spalling, fauling, and join failure. Table 2.1 Composie/flexible and joined concree pavemens disresses Composie/Flexible Pavemen Disresses Joined Concree Pavemens Disress Caegory Disress Type Disress Type Alligaor Cracks Transverse Cracks Corner Breaks Cracking Block Cracks Durabiliy Cracks Longiudinal Cracks Transverse Cracks Edge Cracks Longiudinal Cracks Widening Cracks Paching and Poholes Paching Poholes Surface Defecs Raveling Surface Deformaion Ruing Transverse Join Spalling Join Deficiencies Longiudinal Join Spalling Transverse Join Seal Damage Miscellaneous Pumping Pumping Fauling Mainenance acions Mainenance 2.4. Pavemen Treamens To slow down pavemen deerioraion and reduce coss, prevenive mainenance reamens in an early sage of he pavemen s service life is crucial. According o Zimmerman and Peshkin (2004) ypically applied prevenive mainenance echniques include:
12 For flexible (asphal) pavemen: microsurfacing, chip seals, fog seals, crack reamens, slurry seals, hin ho-mix overlays (less han 1.5 o 2 inches), mill and fill operaions, mainenance of drainage feaures, and ulra hin fricion course; For rigid (concree) pavemen: load ransfer resricion, mainenance of drainage feaures, undersealing, diamond grinding and grooving, and crack and join sealing. Pas research (Zaniewski e al., 1999; Mamlouk and Zaniewski, 1998; Geoffroy, 1996; Labi, 2001; Sharaf and Sinha, 1984) indicaed he need o caegorize mainenance erms and aciviies (e.g., prevenive and correcive mainenance and aciviies). A disincion was also idenified beween major prevenive mainenance (e.g., chip-sealing, hin overlay), which covers a secion of pavemen surface, and minor prevenive mainenance (e.g., join sealing, join/bump repair) which is localized. Table 2.2 and Figure 2.2 presen a proposed characerizaion of pavemen mainenance. Table 2.2 Typical reamens in various caegories of pavemen reamen aciviies (Source: Labi and Sinha, 2003a)
13 Figure 2.2 Pavemen preservaion pracices (Source: Labi and Sinha, 2003a) Figures 2.3 and 2.4 show ypical correcive and prevenive mainenance reamen pracices in Indiana, respecively. The diagrams idenify wheher each correcive or prevenive aciviy is ypically carried ou by conrac (under he capial expendiure accoun) or in-house (under he force-accoun). Figure 2.3 Typical correcive mainenance reamen ypes in Indiana (Source: Labi and Sinha, 2003a)
14 Figure 2.4 Typical prevenive mainenance reamen ypes in Indiana (Source: Labi and Sinha, 2003a) 2.4.1. Flexible Pavemens Waer and moisure are imporan facors in he deerioraion of pavemens. Waer ypically eners he flexible pavemen srucure hrough cracks in he pavemen surface and shoulders and hrough heir longiudinal joins. The ypical prevenive mainenance reamens for flexible pavemens are lised below. Crack sealing and filling: Boh are prevenive mainenance reamens for flexible pavemens. According o he Sraegic Highway Research Program (SHRP; Smih and Romine, 1993 and 1999), crack sealing is defined when specialized maerials are placed ino or above working cracks (using appropriae configuraions o preven debris and moisure inrusion ino he cracks), whereas crack filling is defined when hey are placed ino non-working cracks (o essenially reinforce flexible pavemen and reduce waer infilraion) (Smih and Romine, 1993 and 1999; INDOT, 2008). Mehods o seal and/or fill cracks
15 include rouing he crack o form a reservoir of sealer and using a polymermodified polyeser fiberized asphal for he sealing maerial, or cleaning he debris ou of he crack using compressed air and hen spreading a ho asphal sealer over he crack wih a squeegee (Ponniah and Kennepohl, 1996; Chong and Phang, 1985). Chip sealing: I is defined as a biuminous/asphal maerial and coarse aggregaes full-widh applicaion o preven surface deerioraion and correc exensive cracking and surface failures (INDOT, 1998 and 2008). A layer of small crushed sone is spread on he pavemen, afer spraying i wih an asphal emulsion wih a liquid asphal disribuor. Chip sealing is also used o increase he pavemen s fricion and can be used o correc pavemens suffering from skid resisance loss, raveling, oxidaion and surface permeabiliy. However, chip-sealing is no recommended on high raffic-volume pavemens due o hazards resuling from flying chips, relaively shor life expecancy, roughness and excessive noise (Shuler, 1984). Chip sealing is suggesed (INDOT, 2008) in road secions wih low raffic-volume secions (annual average daily raffic (AADT) of less han 2,000 vehicles/day), surface age of 5 o 8 years, medium Pavemen Condiion Raing (80 o 90 PCR), alligaor cracking, roughness (he pavemen erminal/serviceabiliy index (PSI)) greaer han 3, and low ruing (less han 0.25 inches). Sand sealing: Similar o chip sealing, sand sealing is defined as a full-widh coninuous sealing of he surface wih asphal maerial and aggregae o preven pavemen deerioraion (Mouake e al., 1992). I is ypically preferred on road secions wih relaively few cracks, provides improvemen of he surface by miigaing he effecs of aging, waerproofing and low severiy crack sealing. I is no recommended for applicaion on exising sand surfaces. Sand sealing is considered o be more cos effecive han chip sealing, bu less effecive in erms of performance (Mouake e al., 1992).