• Transportation Life Cycle Assessment Synthesis: Life Cycle Assessment Learning Module Series

      Haselbach, Liv; Langfitt, Quinn (Center for Environmentally Sustainable Transportation in Cold Climates, 2015-03-12)
      The Life Cycle Assessment Learning Module Series is a set of narrated, self-advancing slideshows on various topics related to environmental life cycle assessment (LCA). This research project produced the first 27 of such modules, which are freely available for download on the CESTiCC website http://cem.uaf.edu/cesticc/publications/lca.aspx. Each module is roughly 15- 20 minutes in length and is intended for various uses such as course components, as the main lecture material in a dedicated LCA course, or for independent learning in support of research projects. The series is organized into four overall topical areas, each of which contain a group of overview modules and a group of detailed modules. The A and α groups cover the international standards that define LCA. The B and β groups focus on environmental impact categories. The G and γ groups identify software tools for LCA and provide some tutorials for their use. The T and τ groups introduce topics of interest in the field of transportation LCA. This includes overviews of how LCA is frequently applied in that sector, literature reviews, specific considerations, and software tutorials. Future modules in this category will feature methodological developments and case studies specific to the transportation sector.
    • Use of Cellular Concrete for Air Convection Embankment to Protect Permafrost Foundations in Cold Regions: Feasibility Study

      Liu, Jenny; Wu, Hanli (2019-08-15)
      The air convection embankment (ACE) is a technique used to protect permafrost from thawing in road construction in cold regions. However, the desired materials needed for ACE are not readily available, which prevents its extensive use in Alaska. To overcome the limitation of traditional ACE, and further improve the cooling effect of ACE, this study investigated the feasibility of using cellular concrete as an alternative material for ACE in cold regions. The heat transfer patterns of the cellular concrete ACE, the crushed-rock ACE, and the sand/gravel embankment were studied using the numerical simulation. The results of the present study show that the cooling performance of both cellular concrete ACE and crushed-rock ACE are superior to the traditional sand/gravel embankment. The cellular concrete ACE has better heat insulation property in the summer, and the crushed-rock ACE has stronger natural convection in winter. For the annual cooling efficiency of the two different ACE techniques, the proposed cellular concrete ACE has a better cooling effect on the foundation soil than the crushed-rock ACE. These results indicate that the thermal conductivity and specific heat capacity of construction materials have significant impacts on the performance of the ACE.