The sustainable development of our nation's roadway system requires quantitative means to link infrastructure performance to lifecycle energy use and greenhouse gas (GHG) emissions. Beside surface texture and roughness-induced Pavement-Vehicle Interactions (PVI), we herein recognize that the dissipation of mechanical work provided by the vehicle due to viscous deformation within the pavement structure is a relevant factor contributing to the environmental footprint of pavements. Through a combination of dimensional analysis, experiments and model-based simulations of energy dissipation in pavement structures, the key drivers of deflection-induced PVI are identified. Specifically, a novel experimental setup is developed to study the mechanism of deflection-induced PVI on small-scale silicone elastomer representations of two layered pavement systems, through visual observations of the pavement response and measurements of the dissipated energy. It is shown that the energy which is dissipated when a load moves at a constant speed along a pavement can be reduced to a dimensionless form that scales with the square of the vehicle load, the inverse of the vehicle speed, and relevant elastic and viscoelastic material and structural properties. These experimental findings form the basis for model development in which the pavement is represented as a viscoelastic beam on elastic foundation in a moving coordinate system. Using the experimentally identified dimensionless form of the model, the dimensionless energy dissipation is calibrated against actual pavement materials (concrete and asphalt) considering the specific temperature dependence of the viscoelastic deformation rate of these materials. For engineering applications, the analytical model is employed to calibrate the dimensionless dissipation in function of two material and speed-specific invariants representative of the range of values relevant for pavement engineering and road network analysis. We demonstrate that the derived model -when implemented at a network scale - provides a powerful basis for big data analytics of excess-energy consumption and GHG emission by integrating spatially and temporally varying road conditions, pavement structures, traffic loads and climatic conditions. Implemented for 50,000 lane-miles of the interstate highway system of the State of California, we demonstrate that a ranking based on the inferred GHG-emissions exhibits a power-law data distribution, akin to Zipf's Law, which provides a means to map an optimum path for GHG savings per retrofit at network scale.

An increasing number of agencies, academic institutes, and governmental and industrial bodies are embracing the principles of sustainability in managing their activities and conducting business. Pavement Life-Cycle Assessment contains contributions to the Pavement Life-Cycle Assessment Symposium 2017 (Champaign, IL, USA, 12-13 April 2017) and discusses the current status of as well as future developments for LCA implementation in project- and network-level applications. The papers cover a wide variety of topics: - Recent developments for the regional inventory databases for materials, construction, and maintenance and rehabilitation life-cycle stages and critical challenges - Review of methodological choices and impact on LCA results - Use of LCA in decision making for project selection - Implementation of case studies and lessons learned: agency perspectives - Integration of LCA into pavement management systems (PMS) - Project-level LCA implementation case studies - Network-level LCA applications and critical challenges - Use-phase rolling resistance models and field validation - Uncertainty assessment in all life-cycle stages - Role of PCR and EPDs in the implementation of LCA Pavement Life-Cycle Assessment will be of interest to academics, professionals, and policymakers involved or interested in Highway and Airport Pavements.

An increasing number of agencies, academic institutes, and governmental and industrial bodies are embracing the principles of sustainability in managing their activities. Life Cycle Assessment (LCA) is an approach developed to provide decision support regarding the environmental impact of industrial processes and products. LCA is a field with ongoing research, development and improvement and is being implemented world-wide, particularly in the areas of pavement, roadways and bridges. Pavement, Roadway, and Bridge Life Cycle Assessment 2020 contains the contributions to the International Symposium on Pavement, Roadway, and Bridge Life Cycle Assessment 2020 (Davis, CA, USA, June 3-6, 2020) covering research and practical issues related to pavement, roadway and bridge LCA, including data and tools, asset management, environmental product declarations, procurement, planning, vehicle interaction, and impact of materials, structure, and construction. Pavement, Roadway, and Bridge Life Cycle Assessment 2020 will be of interest to researchers, professionals, and policymakers in academia, industry, and government who are interested in the sustainability of pavements, roadways and bridges.

Responsible for about a third of the annual energy consumption and greenhouse gas (GHG) emissions, the U.S. transportation Network needs to attain a higher level of sustainability. This is particularly true for the roadway Network and the design of pavements in it. Vehicle fuel consumption required to overcome resisting forces due to pavement-vehicle interaction (PVI) is an essential part of life-cycle assessment (LCA) of pavement systems. These PVIs are intimately related to pavement structure and material properties. While various experimental investigations have revealed potential fuel consumption differences between flexible and rigid pavements, there is high uncertainty and high variability in the evaluated impact of pavement deflection on vehicle fuel consumption. This report adopts the perspective that a mechanistic model can contribute to closing the uncertainty gap of PVI in pavement LCA. With this goal in mind, a first-order mechanistic pavement model is considered, and scaling relationships between input parameters and the impact of PVI on vehicle fuel consumption are developed. An original calibration-validation method is established through wave propagation using the complete set of Falling Weight Deflectometer (FWD) time history data from FHWA's Long Term Pavement Performance program (LTPP), representing the U.S. roadway Network. Distributions of model parameters are determined on pavement material properties (top layer and subgrade moduli), structural properties (thickness), and loading conditions obtained from model calibration and the LTPP datasets. These input distributions are used in Monte-Carlo simulations to determine the impact of flexible and rigid pavements on passenger car and truck fuel consumption within the roadway Network. It is shown that rigid pavements behave better than flexible ones in regard to PVI due to higher stiffness. A final comparison with independent field data provides a reality check of the order of magnitude estimates of fuel consumption due to PVI as determined by the model. The calculated change in fuel consumption is used in a comparative LCA of flexible and rigid pavements, and it is shown that the impact of PVI deflection becomes increasingly important for high volume flexible roadways and can surpass GHG emissions due to construction and maintenance of the roadway system in its lifetime.

This book highlights the latest advances, innovations, and applications in the field of LCA in pavements, bridges, and roadways, as presented by leading international researchers at the 6th International Symposium on Pavement, Roadway, and Bridge Life Cycle Assessment (ISPRB LCA2024), held in Arlington, VA, USA, on June 6–8, 2024. It covers a diverse range of topics concerning assessment of environmental impacts of pavements, bridges, and roadways, including environmental product declarations (EPDs) and use of life cycle assessment (LCA) in design, data, and case studies: LCA methodologies for transportation infrastructure, durability and service life assessments, maintenance strategies to enhance performance and minimize environmental impacts, evaluating the environmental impacts of materials and construction, recycling and reuse of materials, carbonation of concrete, pavement vehicle interaction, life cycle thinking in climate change planning, and climate change mitigation. The contributions, which were selected by means of a rigorous international peer-review process, present a wealth of exciting ideas that will open novel research directions and foster new multidisciplinary collaborations.