Conceptual Framework and Trucking Application for Estimating Impact of Congestion on Freight

Abstract

Few analytical techniques fully incorporate freight aspects into transportation system monitoring, system evaluation, and project selection. Transportation investment decisions are frequently based on typical performance measures of travel time and delay for passenger travel, and little, if any, attempt is made to incorporate goods movement into such analysis. Research was performed by the Texas Transportation Institute for a better understanding of freight mobility and reliability issues. The research developed a conceptual framework to help transportation professionals communicate, visualize, and understand factors affecting freight mobility and reliability; a methodology with which to estimate congestion for the conceptual framework; and two applications of the methodology to truck freight (one in Austin, Texas, and one in Denver, Colorado). The conceptual framework visually incorporates the effects of geographic area, commodity type, and time period on freight mobility and reliability. This framework provides a method to communicate freight congestion, mobility, and reliability and can be expanded to include all freight modes (truck, rail, maritime, air, and pipeline). The conceptual framework and methodology can help transportation professionals to better communicate, understand, and make planning-level decisions based on the factors that affect freight mobility and reliability.