Impact of layer thickness variations on pavement performance and life-cycle cost

This study evaluates the impact of asphalt pavement layer thickness variations on structural performance and life-cycle costs. Factors such as materials quality, traffic load, and construction precision affect durability, with layer thickness deviations causing earlier failures and increased life cycle costs. This research combines pavement performance prediction and life-cycle cost analysis (LCCA) of pavements designed by the California Bearing Ratio (CBR) method and the Brazilian mechanistic-empirical (M-E) method. Eight scenarios, including designed and as-built structures, were analyzed based on field-extracted cores. The Monte Carlo method simulated thickness variability, assessing its effect on performance and costs over 120 months, focusing on cracking evolution. The results showed that M-E designs are initially more expensive but offer superior long-term cost-benefit by reducing maintenance. A 10% increase in layer thickness resulted in less maintenance and 63% cost reduction, highlighting economic advantage of better designs. The analysis can include other factors and other M-E methods.