Sequencing and scheduling highway network expansion using a discrete network design model

The motive behind this paper is to produce an NDP model that prescribes the final shape of a transportation network and the sequence and schedule of facility construction during the planning span as well. The proposed bi-level NDP model fills the gap between existing NDP models and practitioners' needs because, in practice, planners have to select investment projects on a year-by-year basis. Conversely, existing models suggest only the optimal network configuration for a planning horizon. A genetic algorithm and a simulated annealing algorithm are proposed along with an exhaustive search algorithm as solution algorithms. Testing these algorithms with an example problem revealed that the simulated annealing worked superiorly to the genetic algorithm. The paper also demonstrates that the model is applicable to a real world problem by showing that the computational time needed to solve the example problem is not prohibitively large.