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8 Figure 2. Process for determining alternatives for consideration in pavement-type selection. It is important that the selection process allows for the con- ways are grouped into one of these classes, depending on sideration of innovative approaches that may be identified by the character of the traffic (i.e., local or long distance) and the pavement industry and other sources. The industry associ- the degree of vehicle access permitted. Some pavement-type ations generally are familiar with the designs and techniques alternatives may not be appropriate for specific functional being used under a variety of conditions and the extent of classes. their success. Therefore, the pavement-type selection commit- Traffic level/composition. The percentage of commercial tee should request input from industry associations. The perfor- traffic and frequency of heavy load applications have a major mance of these innovative approaches needs to be quantified for effect on the alternatives appropriate for a specific proj- the LCCA and M&R schedules used in the LCCA process. The ect. Agencies may choose to establish minimum structural third major component of the alternative identification process requirements to ensure adequate performance and service is a program for monitoring and evaluating the results of ongo- life for minor facilities where traffic is unknown. For heav- ing research programs at both the national and regional levels. ily trafficked facilities in congested locations, the need to minimize the disruptions and hazards to traffic may dictate the selection of strategies having long initial service lives with 3.4 Identification of Alternatives little M&R needed, designed at a high level of reliability. for a Specific Project Existing pavement condition and historical condition Within the broad group of alternatives, certain choices trends. The condition of the existing pavement and its his- may be inappropriate for a specific project under considera- torical performance, as determined through manual or auto- tion. The following factors should be considered in evaluat- mated distress surveys and smoothness testing, can impact ing alternatives for a specific project: the identification of alternatives for both reconstruction and rehabilitation projects. Overall condition indicator values; Functional class. There are three functional classifications: distress types, severities, and amounts; and ride quality mea- arterial, collector, and local roads. All highways and road- surements help define the structural and functional needs of