Derivation of pay adjustment for in-place air void of asphalt pavement from life-cycle cost analysis

The objective of this study is to develop performance-related pay adjustment (PA) for in-place air void of asphalt pavements using pavement management data and life-cycle cost analysis (LCCA). In-place air void data were collected from quality assurance (QA) records for a large number of projects constructed in New Jersey from 1995 to 2005. Pavement condition index data were extracted from pavement management database for the pavement sections where air void data were available. Empirical pavement performance models were developed with sigmoidal functions and used to predict pavement service life. An exponential model form was used to relate the expected pavement service life to the quality measures of in-place air voids. After the rationality of the model was checked, LCCA was performed to derive the PA using different analysis periods and maintenance strategies. Monte Carlo simulations were conducted to capture the variation of PA due to the uncertainty of overlay service life. The PA could be significantly affected by the maintenance strategy if it is estimated using the short analysis period with single overlay, while the PA calculated using the infinite analysis period provides a conservative boundary that is not sensitive to the maintenance strategy. The developed LCCA framework provides the flexibility of determining the PA based on state agencies’ practice on QA and pavement maintenance.