Dissertation Work
My dissertation examines different aspects of the impact of weather-related road closures on the North Carolina road network.
Chapter 1: Analysis of Historical Road Closure Archive (manuscript under review)
Weather-related road closures have the potential to cause serious impacts to society through disrupting road network function (Kermanshah et al. 2014). Most analyses of the impacts of weather-related road closures have focused on short-term, major events, such as hurricanes. There has been little focus on the ability for weather-related disruptions of varying severity (from localized tree fall from high winds to major hurricanes) to cause cumulative impacts to the population over longer time scales. This analysis considers daily impacts to travel time in North Carolina from 2016-2023 by employing a graph theory methodological approach to analyzing local travel. Results indicate that although major events represent the days with the most intense travel time disruptions, the majority of the state has faced significant days with minor travel disruptions, which can become additive over time.
Chapter 2: Impacts of Predicted Flood-related Closures on Rural Travel (in progress)
Rural areas, in particular, often lack important road network redundancy that allows the road network to absorb the effects of road closures without significant impacts to travel within the network, yet these areas are understudied in analyses of flood-related transportation disruption (Shrestha, Pudasaini, and Mussone 2021). This study examines the transportation impacts of both a high-recurrence (10-yr) and low-recurrence (100-yr) flood scenario across rural areas in North Carolina by simulating flow change on road segments using a graph theory shortest-path approach. In addition, this study integrates two different demand scenarios—habitual travel demand for the 10-yr flood scenario and access to hospitals for the 100-yr flood scenario—to account for shifting demand during extreme events. Analysis at the micro-level of individual road segments illuminates shifting travel dynamics across rural areas of the state during flood scenarios.
Chapter 3: Local Road Network Robustness Under Disruption Scenarios (in development)
This chapter “stress tests” each North Carolina census block group’s local road network to determine how many closures are needed to result in network disconnection. Monte Carlo simulations based on road segment vulnerability to tree-fall and flood-related hazards are utilized to create a distribution of the effects of varying numbers of closures.