This volume highlights the latest advances, innovations, and applications in the field of asphalt pavement technology, as presented by leading international researchers and engineers at the 5th International Symposium on Asphalt Pavements & Environment (ISAP 2019 APE Symposium), held in Padua, Italy on September 11-13, 2019. It covers a diverse range of topics concerning materials and technologies for asphalt pavements, designed for sustainability and environmental compatibility: sustainable pavement materials, marginal materials for asphalt pavements, pavement structures, testing methods and performance, maintenance and management methods, urban heat island mitigation, energy harvesting, and Life Cycle Assessment. 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 multidisciplinary collaboration among different specialists.

This synthesis report will be of interest to state, local, and federal agency pavement materials, design, and construction engineers, as well as pavement research engineers and scientists. Those with supervisory oversight for pavement programs will also find it of interest. It describes the current practice for methods to achieve rut-resistant durable pavements. The synthesis documents current experience with permanent deformation of asphalt pavements and identifies methods to improve performance. Information for the synthesis was collected by surveying U.S. and Canadian transportation agencies and by conducting a literature search using domestic and international sources. This report of the Transportation Research Board describes the extent of the rutting problem on the National Highway System, pavement mixture design issues, and the design of rut-resistant mixtures. In addition, alternate mixture types, including stone matrix asphalt and porous asphalt, are discussed, as well as international approaches to mixture design. Finally, the construction of rut-resistant mixtures, including the role of quality control and quality assurance methods, are discussed. A summary of permanent deformation causes and solutions is included in the appendix.

Report for 1922 includes a summarized account of preliminary and organization meetings in 1919,1920 and 1921.