Optimum flexible pavement life-cycle analysis model

A flexible pavement life-cycle model has been developed to yield an optimum maintenance and rehabilitation plan. The model incorporates into the optimization process both performance and cost associated with a life-cycle analysis period for a given pavement structure (project). A single life-cycle indicator called "life-cycle disutility" has been introduced and defined as the ratio of cost to performance. The optimum plan is the one associated with the minimum life-cycle disutility value. The model evaluates several potential maintenance and rehabilitaton plans generated according to two defined decision policy options. The first decision policy option requires a fixed analysis period, whereas the second one involves a variable analysis period. Both options require a specified number of major rehabilitation cycles. Pavement life-cycle cost includes initial construction, scheduled major rehabilitation cycles, and routine maintenance and added user cost. Pavement life-cycle performance is defined as the area under the life-cycle performance curve either generated from actual pavement distress data or based on an incremental analysis of the American Association of State Highway and Transportation Officials basic design equation of flexible pavement.