The time period over which alternate design strategies are analyzed. Often, agencies can use past local experience to estimate these parameters.
Because LCCA is performed in advance of actual pavement construction, estimates of pavement performance (e.g., how will a pavement deteriorate over time) and maintenance and rehabilitation effort timing (e.g., when should maintenance and rehabilitation activities be scheduled) need to be made so that an appropriate analysis period can be chosen and appropriate cost estimates made. Determine performance periods and activity timing.LCCA is most often used to evaluate two or more different pavement design strategies and determine their relative value. A “pavement design strategy” is the combination of initial pavement design and necessary supporting maintenance and rehabilitation activities. Alternative pavement design strategies.These decisions, estimates and assumptions can be broadly categorized as follows: The following subsections describe the general steps involved in a LCCA.Ĭertain baseline decisions, estimates and assumptions are needed in order to establish the parameters under which a LCCA can be carried out. The end result of a successful LCCA is not simply the selection of one alternative over the other but the selection of the most cost-effective design strategy for a given situation and a greater understanding of the factors that influence cost effectiveness. Original design strategy alternatives should be reevaluated base on these results analysis in order to improve the cost-effectiveness of each alternative. A sensitivity analysis is often used to do this. Results should be scrutinized for the most influential costs, factors and assumptions. Analyze the results and reevaluate alternatives.Comparison usually involves expressing each alternative using a common metric such as net present value (NPV) or benefit-cost ratio (B/C). Costs associated with the owning agency and users are calculated for each alternative. Certain baseline decisions, estimates and assumptions are needed in order to establish the parameters under which a LCCA can be carried out. Make initial strategy and analysis decisions.Typically, LCCA involves the following basic steps: LCCA should be used as a decision support tool when selecting pavement type, determining structure and mix type (for flexible pavements), construction methods, as well as maintenance and rehabilitation strategy. It attempts to identify the best value (the lowest long-term cost that satisfies the performance objective being sought) for investment expenditures.” It incorporates initial and discounted future agency, user, and other relevant costs over the life of alternative investments. “…an analysis technique that builds on the well-founded principles of economic analysis to evaluate the over-all-long-term economic efficiency between competing alternative investment options.
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