Impact of Improved Density on Pavement Design Response for Low-Volume Roads/Non-Primary Routes

Abstract

Hughes said “Compaction is the single most important factor that affects pavement performance in terms of durability, fatigue life, resistance to deformation, strength, and moisture damage.” Past research studies have shown that a 1% decrease in air voids was estimated to improve the fatigue performance of asphalt pavements between 8.2% and 43.8%. Tran et al. quoted: “A 1% decrease in air voids was estimated to extend the service by conservatively 10% .” The objective of this research study is to show the impact of varying density properties using the concept of expected life difference. Fatigue life will be evaluated using the traditional fatigue life prediction equations and an advanced mechanistic empirical model (i.e., AASHTO Pavement ME). Dynamic modulus is the main input for conducting a pavement analysis and/or design when using AASHTO Pavement ME. The dynamic modulus data was generated from an extensive laboratory density study sponsored by Kentucky Transportation Cabinet. The air voids of the dynamic modulus samples varied from 11.4% to 3.9%. This study forms a framework for a highway agency, city, and county engineer if they are looking for an engineering solution as to why they should improve their in-place density specifications and what that impact is, using mechanistic empirical design procedures.