Field evaluation of porous asphalt course for life-cycle cost analysis

Abstract

Porous asphalt courses (PAC) provide environmental and safety benefits by reducing traffic noise and improving drainability. As pressure increases on the cost and availability of natural resources, a greater understanding is needed of field performance to allow maintenance and preservation of resilient, sustainable and economic networks. The main purpose of this paper is to utilize life-cycle cost analysis (LCCA) as a decision-support tool for three pavement rehabilitation strategies. These alternatives included open-graded friction course using natural aggregate (OGFC), porous asphalt course using natural aggregate (PAC), and porous asphalt course using steel slag (SS-PAC). The LCCA followed the Federal Highway Administration’s RealCost procedure and incorporated information collected from highway agencies. Based on the results of the performance analysis, pavement life-cycle models were developed for each alternative. Using the life-cycle models and historical unit costs, deterministic and probabilistic LCCAs were conducted. The results demonstrated the cost saving of SS-PAC in both low and medium price ranges. In order to have economic benefits, the service life of SS-PAC needed to be more than eight years for a high price range. SS-PAC had a 78 and 92 percent chance of being more cost-effective than OGFC and PAC according statistical analysis, respectively. Conclusions from the LCCA supported use of the SS-PAC alternative since SS-PAC was shown to be relatively cost-effective over the 40-year analysis period. Utilization of the SS-PAC alternative would combine cost efficiency and sustainability for highway projects, especially rehabilitation and reconstruction.