Author Description

The national pavement network is a key component of the transportation infrastructure that the U.S. economy depends on for mobility and movement of goods. Minimization of the environmental and social impact of its maintenance and operation is an important goal. In this dissertation study, a life cycle assessment (LCA) approach was used to evaluate the effects of the selection and timing of pavement maintenance and rehabilitation (M & R) strategies on reducing energy consumption and greenhouse gas (GHG) emissions. The omission of the use phase in the pavement life cycle and the lack of a rolling resistance model to address the additional vehicle fuel consumption and the resultant GHG emissions, primarily CO2, have been a significant problem among previous studies. With the special focus on rolling resistance in the use phase, this dissertation study applied a life cycle approach to evaluate the energy consumption and CO2 emission associated with the pavement M & R strategies at both project level and network level. The LCA in this study covered the material production phase, construction phase, and use phase in the pavement life cycle. By deepening the understanding of the relationship among pavement surface characteristics, pavement-induced rolling resistance, and vehicle fuel use, this dissertation answered the following questions: 1) at a project level, how does rolling resistance affect CO2 emissions and energy use and what are the important factors; 2) at a network level, what roughness (using International Roughness Index, IRI) triggering values for M & R should be used to maximize the CO2 emission reduction, and how much CO2 emission reduction can be achieved; and 3) does pavement roughness have a significant impact on vehicle speed? Four project-level case studies of Caltrans Capital Preventive Maintenance (CAPM) treatments were evaluated. In the case studies, the CAPM treatments were compared with an alternative strategy where no treatment occurs (Do Nothing