Guidelines for the Use of Pavement Warranties on Highway Construction Projects (2011)

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51 Design–Bid–Build: The traditional contract delivery system where the owner contracts with separate entities for design and construction services. The construction contract is awarded based on the low bid, and the project is constructed using method specifications. Using a warranty under this system, the contractor may take responsibility for the mix design, but the owner retains the majority of the performance risk. Design–Build: A delivery system in which a single entity designs and constructs a project based on conceptual plans, design criteria, and performance specifications established by the owner. The procure- ment approach may range from low bid to best value where price and other factors are considered in the selection. Using a warranty under this system, the contractor takes responsibility for design, both mix and structural within certain parameters, and assumes greater risk for performance. Design–Build–Operate–Maintain (Public–Private Partnership): A contract delivery system where a single entity designs, constructs, maintains, and operates (and finances) a project for a specified duration, usually the life cycle of the pavement or longer, based on technical criteria and performance requirements established by the owner. The procurement process may entail a qualifications-based selection and a negotiated process to reach agreement on price and other commercial terms. Under this system, the contractor (or developer/concessionaire) takes primary responsibility for the pavement performance. Equivalent Single Axle Load (ESAL): A type of load quantification that converts wheel loads of various magnitudes and repetitions (mixed traffic) to an equivalent number of standard or equivalent loads based on the amount of damage they do to the pavement. Hot Mix Asphalt (HMA): Refers to flexible pavements. The terms “bituminous” and “asphalt” are used interchangeably. International Roughness Index (IRI): A worldwide standard for mea- suring pavement smoothness. The index measures ride comfort in terms of road roughness using the number of inches per mile that a laser, mounted in a specialized van, jumps as it is driven on the roadway. Longitudinal Cracking: A pavement distress in which cracks are predominantly parallel to pavement centerline. Method Specification: Also called recipe specifications, or prescriptive specifications, method specifications require that the contractor use specified materials in definite proportions and specific types of equipment and methods to place the material (Transportation Research Circular E-C074, 2005). Pavement Distress Index (PDI): A combined index of pavement surface distress combining IRI and other roughness distress indices. Portland Cement Concrete (PCC): Refers to rigid pavements placed on a subgrade or underlying base course. Performance Indicators: Distresses, properties, or functional charac- teristics of a warranted pavement that can be measured and are linked to the performance of the pavement. Performance Specification: Performance specifications state require- ments in terms of the required results with criteria for verifying compliance, without stating the methods for achieving the required results. In the broadest terms, a performance specification defines the performance characteristics of the final product and links them to construction, materials, and other items under the contractor control (FHWA, 2004). Performance Warranties: Specifications that hold the contractor fully responsible for product performance during the warranty period. Under performance warranties, the contractor guarantees that the pavement will perform at a desired quality level. The contractor assumes some level of responsibility, depending on the specific project, for structural pavement or mix decisions (Transportation Research Circular E-C074, 2005). Potholes: A pavement distress in which bowl-shaped holes of various sizes develop in the pavement surface. Raveling: A pavement distress in which the pavement surface is worn away by the dislodging of aggregate particles and the loss of asphalt binder. Reflective Cracking at Joints: A pavement distress in which cracks in asphalt concrete overlay surfaces that occur over joints in concrete. Rutting: A pavement distress in which a longitudinal surface depression develops in the wheel path. Threshold: Measurable tolerance or limit for performance (distress or functional) indicators. Transverse Cracking: A pavement distress in which cracks are pre- dominantly perpendicular to pavement centerline. Type 1 (Materials and Workmanship) Warranty: A warranty imple- mented in conjunction with standard, method specifications. Type 1 warranties require the contractor to correct early defects in the pavement caused by elements within the contractor’s control, namely the materials and workmanship of construction. The DOT uses a traditional low-bid contract where the contractor assumes minimal performance risk. The warranty durations are relatively short-term, typically three years or less. Glossary

Type 2 (Short-Term Performance) Warranty: A warranty that shifts more responsibility to the contractor for certain aspects of pave- ment performance during the warranty period. Type 2 warranties are implemented under traditional low-bid or alternative design– build contracts. They are the broadest category of warranties, as the amount of responsibility shifted to the contractor can range from design of the mix to design of structural aspects of the pavement, particularly when combined with an alternative design–build contract. Their provisions typically include elements of both method and performance specifications but can vary between method-based or performance-based. Type 2 warranty durations generally fall within the range of 5 to 10 years. Type 3 (Long-Term Performance Warranty): A warranty that shifts the responsibility for the long-term pavement performance to the contractor. Type 3 warranties typically use high-level performance criteria establishing pavement performance standards or thresholds that the contractor must maintain for the service life of the pavement or beyond, and include planned and unplanned maintenance. They are implemented under alternative design–build–warrant, performance-based maintenance, or public–private partnership agreements, and are typically 20 years or longer in duration. Warranty: A guarantee of the integrity of a product and of responsi- bility for the repair or replacement of defects by the contractor (Hancher, 1994). 52