Life cycle cost analysis on airport pavement design with different types of materials

Abstract

This study is about airport pavement design using a life-cycle cost analysis. Secondary data collected for the pavement design includes: (i) annual air traffic; (ii) traffic growth factor; (iii) sub-grade strength of 12,000 Psi; and (iv) design life of 20, 30, and 40 years. FAARFIELD software is used to design flexible and rigid pavements, using alternative materials for different layers as prescribed by FAARFIELD. The initial costs and life- cycle costs of the pavements are determined using AirCost software’s material unit price. For the long-term (40-year) analysis period, overlay design incorporates primarily selective pavements: (i) asphalt and concrete overlays on flexible pavement, and (ii) asphalt and concrete overlays on rigid pavement. Pavement life-cycle cost analysis was done using two methods: (i) Net Present Value method and (ii) Deterministic and Normal Probabilistic method in AirCost software. A single discount rate was used for the analysis The study identifies cost-effective flexible and rigid pavement design materials. Another significant finding was the use of recycled concrete aggregate as a subbase design material on both pavements. The life-cycle cost analysis determines flexible pavement has lower initial costs of 12.4%, 13.88%, and 14.93% but higher maintenance and rehabilitation costs of 7.82%, 8.73%, and 8.08% than rigid pavement. Therefore, the rigid pavement with a single Portland cement concrete overlay is the most cost-effective pavement alternative (NPVs of 4.41%, 4.45%, 3.73%, and AirCosts of 19.09%, 19.24%, and 18.45%, respectively) and has the highest chance of success with less simplified risk. Furthermore, sensitivity analysis reveals that as the discount rate rises, the life cycle cost falls.