Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 20
20 CHAPTER 5 Selection of Preferred Pavement Alternatives 5.1 Overview · Conversely, if the differences between all or some of the alternatives are not significant, then the similar alter- Upon completion of the LCCA, the alternatives are evalu- natives could be considered for alternate pavement- ated using economic and noneconomic factors to select the type bidding. preferred pavement type(s). The outcome of this process is a single preferred pavement type for traditional design-bid-build projects and multiple preferred pavement types for alternative 5.2 Economic Selection Factors bid projects, which are consistent with the agencies financial An important step in the selection of the preferred strategy goals, policy decisions, and experience. is the consideration of the financial aspects of the project. The Figure 15 presents a flow chart of the proposed approach for agency evaluates the pavement-type alternatives on the basis of selecting preferred pavement types, and this chapter presents a these aspects and their importance. The following list describes detailed discussion. The selection process is outlined as follows: the economic factors that should be included in the evaluation: 1. The alternatives are evaluated using the economic factors; · Initial costs. Agencies may set maximum funding levels alternatives that fail to meet the economic criteria are for individual projects so that the entire system can be eliminated. 2. The alternatives that meet the economic criteria are eval- maintained at a desired level. Such constraints may result uated using the noneconomic factors. in eliminating some alternatives, particularly those with · If an alternative fails to meet the noneconomic criteria, high initial costs, even if the alternatives are attractive from further evaluation may be necessary to ascertain whether a life-cycle cost perspective. The evaluation should deter- the noneconomic factors unduly override its inclusion. If mine if the first costs of an alternative exceed the available the risks from noneconomic factors outweigh the eco- resources or would impact the management of the overall nomic advantages, the alternative is eliminated. system. · If there are no noneconomic factors to override its inclu- · Rehabilitation costs. Certain alternatives may provide a sion, the alternative is selected as a qualified alternative. low overall life-cycle cost but require several rehabilitation 3. The alternatives that meet both economic and noneconomic activities to maintain the desired functional and structural criteria are considered as qualifying alternatives. performance level. Such costs may have an impact on the · If there is only a single qualifying alternative, it is selected management of the entire system. Frequent interventions as the most-preferred alternative. also may result in higher work zone user costs and impacts 4. When there are two or more qualified alternatives, then the on local business and community. The evaluation should economic and noneconomic aspects of these alternatives are determine if an alternative that requires frequent rehabili- weighed using an alternative-preference screening matrix to tation actions may be suitable for the project. identify the most preferred type. The screening matrix is · Maintenance costs. Certain alternatives may require a dis- used to evaluate if there are considerable differences among proportionate maintenance effort over their lifetime that the alternatives. exceeds the resources available for applying the mainte- · If there is a clear cut preference among the alternatives, nance. The evaluation should focus on the maintenance the most advantageous alternative is recommended for actions that an alternative may require to maintain per- selection. formance levels over its life.