• A Framework for Life Cycle Sustainability Assessment of Road Salt Used in Winter Maintenance Operations

      Cui, Na; Xie, Ning; Shi, Xianming (Center for Environmentally Sustainable Transportation in Cold Climates, 2016-12)
      It is important to assess from a holistic perspective the sustainability of road salt widely used in winter road maintenance (WRM) operations. The importance becomes increasingly apparent in light of competing priorities faced by roadway agencies, the need for collaborative decision-making, and growing concerns over the risks that road salt poses for motor vehicles, transportation infrastructure, and the natural environment. This project introduces the concept of Life Cycle Sustainability Assessment (LCSA), which combines Life Cycle Costing, Environmental Life Cycle Assessment, and Social Life Cycle Assessment. The combination captures the features of three pillars in sustainability: economic development, environmental preservation, and social progress. With this framework, it is possible to enable more informed and balanced decisions by considering the entire life cycle of road salt and accounting for the indirect impacts of applying road salt for snow and ice control. This project proposes a LCSA framework of road salt, which examines the three branches of LCSA, their relationships in the integrated framework, and the complexities and caveats in the LCSA. While this framework is a first step in the right direction, we envision that it will be improved and enriched by continued research and may serve as a template for the LCSA of other WRM products, technologies, and practices.
    • Prediction of Thermal Behavior of Pervious Concrete Pavements in Winter

      Chen, Zhao; Nantasai, Benjamin; Nassiri, Somayeh; Haselbach, Liv (Center for Environmentally Sustainable Transportation in Cold Climates, 2017-05-15)
      Because application of pervious concrete pavement (PCPs) has extended to cold-climate regions of the United States, the safety and mobility of PCP installations during the winter season need to be maintained. Timely application of salt, anti-icing, and deicing agents for ice/snow control is most effective in providing sufficient surface friction when done at a suitable pavement surface temperature. The aim of this project was to determine the thermal properties of PCP during the winter season, and to develop a theoretical model to predict PCP surface temperature. The project included a laboratory and a field component. In the laboratory, thermal conductivity of pervious concrete was determined. A linear relationship was established between thermal conductivity and porosity for pervious concrete specimens. In the field, the pavement temperature in a PCP sidewalk installation at Washington State University was monitored via in-pavement instrumentation. Based on the field data, the Enhanced Integrated Climatic Model (EICM) was developed and validated for the site, using PCP thermal properties and local climatic data. The EICM-predicted PCP surface temperature during the winter season agreed well with the field temperature. Overall, the predicted number of days that the pavement surface fell below 32°F agreed well with the number based on field data for 85% of the days. Therefore, the developed model is useful in identifying those days to apply deicer agents. Finally, a regression model using climatic indices was developed for PCP surface temperature prediction in the absence of a more advanced temperature model.
    • Recent Advances in Sustainable Winter Road Operations – A Book Proposal

      Shi, Xianming (Center for Environmentally Sustainable Transportation in Cold Climates, 2017-08)
      Investing in winter transportation operations is essential and beneficial to the public and the economy. The U.S. economy cannot afford the cost of shutting down highways, airports, etc., during winter weather. In the northern U.S. and other cold-climate areas, winter maintenance operations are essential to ensure the safety, mobility, and productivity of transportation systems. Agencies are continually challenged to provide a high level of service and improve safety and mobility in a fiscally and environmentally responsible manner. To this end, it is desirable to use the most recent advances in the application of materials, practices, equipment, and other technologies. Such best practices are expected to improve the effectiveness and efficiency of winter operations, to optimize material usage, and to reduce associated annual spending, corrosion, and environmental impacts. Currently, no professional societies, scientific journals, or textbooks are dedicated solely to sustainable winter road operations, and key information is scattered across a variety of disciplines. The objective of the proposed book is to summarize the best practices and recent advances in sustainable winter road operations for the purposes of education and workforce development. This book is now in press and can be cited as follows: Shi, X., Fu, L. (2017). Sustainable Winter Road Operations (Eds.). ISBN: 978-1-119-18506-2. Wiley-Blackwell.