Performance Measures of Road Infrastructures

Licentiatavhandling, 2017

Roads are transport infrastructures that play a fundamental role in the development of societies and businesses. They are valuable assets, as they connect places, provide mobility, create jobs and stimulate economic prosperity. Although road infrastructures have shown various positive impacts throughout the decades, they require various resources for building, operation and maintenance. Moreover, due to their long, almost never-ending, lifetime, their environmental and economic impacts are important in support of achieving climate change mitigation and cost optimization goals. In order to achieve these goals, as for other transport infrastructure, a holistic approach is needed to understand the challenges connecting environmental, societal and economic impacts, for both existing and future roads, and develop consistent strategies toward the overall aim of sustainability. The present licentiate thesis evaluates the environmental and economic assessment of Norwegian roads, both new and existing, using two well-established methodologies: environmental life cycle assessment (LCA) and life cycle cost analysis (LCCA). The main focus of the thesis is on open-road infrastructure, while road tunnels and bridges are excluded from investigation. A scientific literature review of LCA and LCCA was conducted using qualitative research analysis related to road infrastructure. The review identified and summarized key findings and highlighted strengths and weaknesses of papers in the domain of LCA and LCCA. In addition, three types of LCA software tools that are currently used/tested in Norwegian road projects were evaluated on a hypothetical open-road case and the results were further discussed with respect to their area of coverage and methodologies. Furthermore, the lifetime of different pavement mixes were estimated in three selected counties in Norway to identify the effect of different covariates in the lifetime expectancy of pavement. Here lifetime is defined as the period of time from laying a new pavement or building a complete new road until the in-service pavement/road fails according to road condition criterion.