Electronic Theses and Dissertations

Multi-Period Transportation Network Investment Decision-Making Using Link Ranking and an Econometric Framework

Khademul Haque

Data is provided by the student.

Abstract

Prospective transportation infrastructure projects take numerous years of planning before they are scheduled for construction. Moreover, limited funds are forcing national, regional and local governments to carefully prioritize their investments. Therefore, reliable quantitative tools are needed to help decision-makers choose their investments so that the allocation of available resources is optimized. Prioritization of projects over a multi-period planning horizon is a difficult task given a limited budget and an exhaustive set of possible combinations of when each project will be scheduled for construction. Although multi-period network investment is studied in the literature, its application by public agencies is limited because of the complexities involved in network design problems and the computational time needed to analyze large-scale networks. The contribution of this research is two-fold. First, to understand the relative importance of individual links in a road network and suggest a methodology to rank the links according to importance factors while combining the network improvement investment decisions and subsequent network user response in a feedback loop. One importance factor is based on the link flows at equilibrium. Another factor is based on the importance of the facilities served. A third factor is based on the number of origin-destination pairs served by a link. The proposed methodology is demonstrated with a small test network and a real-scale transportation network. The author performed sensitivity analysis using various budget scenarios and found that, with an increase in budget, the ranking of critical links changes. The second contribution is to extend the single-year discrete network design formulation to a multi-period network design problem (MPNDP) to understand the spatial and temporal patterns in which multi-period network investments are made. Then, using the MPNDP investment results and the network characteristics, the research proposes to utilize an alternate methodology called a Multi-Period Econometric Network Investment Model (MENIM) with which agencies can obtain approximate network investments that are reasonably comparable to the MPNDP. Six medium-to-large scale networks are analyzed using the MPNDP, and the results are used to develop the econometric model. Two additional networks are used to validate the MENIM. Patterns of multi-period network investments from the numerical analysis are extensively discussed along with policy recommendations for public agencies.