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1 Pavement warranties were common across the United States in the early 1900s and then again in the 1950s during the construction of the interstate system. However, they fell out of favor until the 1990s when federal regulations allowed state highway agencies (SHAs) to implement pavement warranties on federally funded projects. Meanwhile, several European (and other) agencies have had success with pavement warranties for more than 60 years. The success in Europe, coupled with revised federal regulations, has supported the increased use of warranties in the United States over the last several decades. In general, there are two types of pavement warranties: (1) materials and workmanship and (2) performance. As the name implies, materials and workmanship warranties include requirements to correct pavement defects based on quality materials and standard practices that are in direct control of the contractor, typically over a 1-year time frame. Performance- based warranties are also applicable to materials and workmanship within control of the contractor but apply an added level of performance and pavement condition threshold criteria that must be met during and at the end of the warranty period. Warranty periods for performance-based warranties typically range from 2 to 20 years, depending on the treatment (preservation, rehabilitation, new or reconstruction) and contract type (e.g., design-bid-build, design-build, public-private partnerships). Although pavement warranties have been in use for decades, there is no national pave- ment warranty standard. Agencies have typically developed their own pavement warranty specifications. Not surprisingly, agency specifications vary by pavement type, warranty type, warranty period, risk allocation item, performance evaluation method, and enforce- ment method. Pavement performance indicators have primarily focused on structural capacity, func- tional performance, and safety. Developed performance indicators generally include pave- ment distress (e.g., cracking, rutting, faulting), surface friction characterization, and ride quality (e.g., International Roughness Index [IRI]). Threshold values are established for each performance indicator for each pavement type and are typically assessed both annually and at the end of the warranty period. When a threshold value is exceeded, an assessment is made on potential courses of correction, and if necessary, remedial work is conducted to mitigate the distress or pavement condition. The objective of this synthesis is to document agency practices associated with the use of performance-based pavement warranties, focusing on asphalt and concrete pavement projects (new, preservation, and rehabilitation) with warranty periods of at least 1 year. This synthesis is based on the combined results of a literature review of performance- based pavement warranties, a survey of highway transportation agencies (U.S. highway S U M M A R Y Performance-Based Pavement Warranty Practices
2 Performance-Based Pavement Warranty Practices agencies and Canadian provincial and territorial governments), and follow-up questions with agencies who indicated current use of performance-based pavement warranties. In total, 50 highway transportation agencies (44 U.S. and 6 Canadian) provided responses to the agency survey (total U.S. response rate of 86%). Of the 50 responding agencies, 32 indicated previously using pavement warranties; however, of these agencies, only 18 indicated that warranties are currently being used in pavement construction. For those agencies that have not considered or no longer use pave- ment warranties, the primary reasons limiting use was the need for consistent monitoring of pavement distress, concern with cost-effectiveness, and impact to contractor bonding capacity. For the 18 agencies who indicated current pavement warranty use, the main objectives of warranty implementation included increasing quality and shifting more risk to the contractor. Projects selected for pavement warranties are often based on treatment type (new or reconstruction, rehabilitation, and preservation), existing pavement con- dition for preservation and rehabilitation projects, site conditions, and traffic volumes. During the development of pavement performance criteria, agencies primarily based cri- teria on pavement management data and engineering judgment. During the design and construction phases, most agencies indicated the contractor is responsible for mix design, and to a lesser extent, pavement thickness design and pavement or treatment type selec- tion. These 18 agencies also indicated pavement warranties provided benefits related to transferring risk to the contractor, reducing pavement failures, improving contractor workmanship, and improving pavement performance. Conversely, agencies indicated several implementation challenges including condition assessment, industry resistance, and defining threshold values. To showcase agency pavement warranty practices, five case examples were developed highlighting agency practices related to project selection criteria, overall warranty pro- cess, responsibilities, dispute resolution, pavement inspection, and specifications. The case examples highlighted pavement warranty practices for Alberta Transportation, Florida Department of Transportation (FDOT), Michigan DOT (MDOT), Pennsylvania DOT (PennDOT), and West Virginia Division of Highways (WVDOH). The Alberta Transporta- tion case example highlights pavement warranty requirements for new asphalt and concrete pavements for design-build-finance-operate (DBFO) projects. The FDOT case example showcases warranty requirements for asphalt pavement surface and friction course layers and new and reconstructed concrete pavements; the MDOT case example showcases war- ranty requirements for new and reconstructed asphalt and concrete pavements, asphalt pavement preservation, and asphalt pavement rehabilitation; the PennDOT case example showcases new and reconstructed asphalt pavements; and the WVDOH case example showcases new and reconstruction asphalt and concrete pavements. Unfortunately, of the agencies responding to the survey, none reported or provided warranty information requirements specific to concrete pavement preservation and rehabilitation. Although several agencies have developed pavement warranty specifications and have successfully implemented their use, it is still difficult to accurately quantify not only the cost of warranties, but also their overall impact on pavement performance.
