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8 What Are 3R Projects? This chapter discusses the definition of 3R projects and how they differ from new construction and reconstruction projects; the objectives of 3R projects; and typical improvements considered in 3R projects in addition to resurfacing. 2.1 New Construction Versus Reconstruction Versus 3R Projects Understanding of the context for design of 3R projects requires understanding of the distinc- tions between new construction, reconstruction, and 3R work. Each of these types of projects is defined below. 2.1.1 New Construction Projects New construction projects typically consist of projects on new alignment where no highway facility has existed before (e.g., projects on greenfield sites). Some projects on existing roads might be classified as new construction if the existing roadway is completely removed, a new alignment or cross section is developed for the facility, and the new alignment and cross section are not substantially constrained by development adjoining the existing road; this situation is rare, but can occur. The criteria in the AASHTO Green Book (4) are used to design new construction projects. The design guidelines presented in this report do not apply to new construction projects. 2.1.2 Reconstruction Projects Reconstruction projects include projects on existing roads that are not considered new construction and in which ⢠A substantial proportion of the existing alignment is modified, or ⢠The basic roadway cross section is changed (e.g., expanding an existing two-lane highway to four lanes). The criteria in the AASHTO Green Book (4) are used to design reconstruction. The design guidelines presented in this report do not apply to reconstruction projects. For purposes of the design guidelines presented in this report, projects that add a median to an existing undivided facility or that widen an existing median are considered reconstruction projects. 2.1.3 3R Projects Resurfacing, restoration, and rehabilitation projects include projects in which the scope is limited to resurfacing, restoration, or rehabilitation of existing roads; as defined above, C H A P T E R  2
What Are 3R Projects? 9Â Â 3R projects do not involve new construction or reconstruction. Therefore, by definition, 3R projects do not involve a substantial amount of road construction on a new alignment, removal of the entire pavement structure down to the subgrade, realignment of substantial portions of the project, or a change in the basic roadway cross section. If only a limited or isolated portion of a project involves new construction or reconstruction, the remainder of the project can be designed as 3R work. The assessment as to which portions of a project involve new construction, reconstruction, or 3R work is left to the discretion of individual agencies. Projects with overlays of any depth and projects involving cold milling to remove an obsolete surface course or maintain a pavement surface elevation consistent with vertical clearance design may be considered 3R projects. For purposes of the design guidelines presented in this report, projects may be classified as 3R regardless of whether they are funded as part of the federal 3R program or any other designated 3R program. The design guidelines presented here are applicable to projects that are not considered new construction or reconstruction and involve only resurfacing, restoration, or rehabilitation, regardless of the project funding source. 2.2 Objectives of 3R Projects The primary objective of most 3R projects is to preserve and extend the life of the pavement by resurfacing. Thus, 3R projects are normally initiated because pavement management systems indicate the need for pavement resurfacing. Furthermore, the timing of most 3R projects is based on the timing of the need for pavement resurfacing to preserve and extend the life of the pavement structure. A few 3R projects are initiated to address needs other than pavement resurfacing; as long as such projects do not involve new construction or reconstruction, they can be considered as 3R projects for design purposes. While the primary objective of most 3R projects is pavement preservation, the develop- ment of a 3R project provides an opportunity for geometric improvements to enhance traffic operations, reduce crashes, improve drainage, or improve the roadway or roadside in other ways. The project would still be considered 3R work as long as the design changes do not constitute new construction or reconstruction. It is to the advantage of both the highway agency and the traveling public for any needed design changes to be made in conjunction with the pavement resurfacing project. As compared with implementing separate projects at separate times, coordination of such improvements reduces implementation costs, reduces the duration of construction, and reduces travel delays in work zones. Federal law requires highway agencies to consider the need for traffic operational and safety improvements in the project development process for 3R projects funded through the federal 3R program. The guidelines presented in this report document a structured process for considering the need for traffic operational and safety improvements in 3R projects that is intended to focus such improvements on locations where the improvement will be cost-effective. The guidelines indicate that design improvements should not necessarily be made in all 3R projects; rather, design improvements should be made only when engineering analyses confirm that the pro- posed improvements are appropriate and cost-effective or where a specific need is other wise demonstrated. 2.3 Typical Improvements Made in 3R Projects in Addition to Resurfacing A broad range of highway infrastructure improvements may be considered in 3R projects in conjunction with pavement resurfacing. A recent survey found that most highway agencies routinely consider the need for specific design improvements intended to reduce crash frequency
10 Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects and severity in 3R projects (7). Another survey identified the types of design improvements most commonly cited by highway agencies as among the top five types of improvement made in conjunction with 3R projects (7, 8). These include ⢠Guardrail addition or improvement (including improvement of guardrail end treatments); ⢠Shoulder paving, grading, or widening; ⢠Clear zone improvements; ⢠Signage improvements; ⢠Shoulder or centerline rumble strips; ⢠Striping and delineation; ⢠Superelevation restoration; ⢠Pavement surface condition/friction; ⢠Intersection design/turn lanes/turn radius; ⢠Roadway/lane widening; and ⢠Roadside slope flattening. These improvement types and others that may be incorporated in 3R projects are addressed in Chapter 6 of these guidelines.
