Determination of optimum pavement construction alternatives to minimize life-cycle costs and greenhouse gas emissions

The selection of highway pavement design and construction strategies traditionally are based on the life-cycle cost analysis (LCCA) of different alternatives. However, with the growing concerns on sustainable development, the environmental aspects of these alternatives start to attract more attention, and even become the essential component of Decision making criteria. The objective of this study was to assess long-life pavement design strategies based on the principles of sustainability, in particular costs and greenhouse gas (GHG) emissions. The evaluation process consists of three steps: design simulation, life-cycle cost analysis (LCCA) and life-cycle assessment (LCA) that focuses on the environmental effects of different alternatives. A multibillion dollar major road construction project currently being implemented in Hong Kong was chosen as a case study to illustrate the analysis procedure. The results show that the integration of design simulations and LCCA and LCA models is effective to predict the economic and environmental performance of road construction projects. The analysis enables decision makers to understand the sustainable implications of different pavement design strategies, as well as to identify a solution that optimizes the needs for cost saving and environmental conservation.