Probabilistic Life-Cycle Cost of Pavements Characterization and Application of Parameter Input Variation for Scenarios

Life Cycle Cost Analysis (LCCA) evaluates the economic performance of alternative pavement investments. Currently, practitioners treat input parameters as static, deterministic values, which although computationally simpler, will hide the implicit uncertainty underlying the analysis. Over the past decade, an emphasis has been placed upon accounting for uncertainty by treating input parameters as probabilistic, rather than deterministic, values. This research builds upon existing pavement LCCA work by probabilistically characterizing several sources of uncertainty, including unit-cost of construction activities, pavement deterioration, and forecasting of future material prices. The probabilistically characterized input parameters have subsequently been implemented in three concrete pavement case studies which vary in terms of analysis period. For each case study, uncertainty has been propagated to characterize the difference in life-cycle costs and has been used to elicit which input parameters are significant contributors to the overall life-cycle cost uncertainty in each scenario. From the analysis, uncertainty surrounding unit-cost is the dominant driver of variation across all scenarios, significantly outweighing the impact of the many other input parameters considered; this suggests practitioners should focus their efforts on deriving statistical characterization methods to reduce its variation, if possible, rather than focusing their efforts on more trivial uncertain parameters