Crossing elimination is a relatively recent strategy that emergency managers and departments of transportation may consider during no-notice evacuations. In this strategy, certain movements at intersections that may be permissible under normal operating conditions are prohibited to increase the flow of traffic on arterial roadways. A few previous studies examined this strategy in conjunction with contraflow operations. However, the benefits of crossing elimination alone remain unclear. This study helps fill this gap in knowledge by assessing the effects of intersection crossing elimination during evacuations. In this study, a bi-level model involving optimization and simulation was developed to determine the near-optimal configuration of intersection movements from a set of pre-specified possible configurations for intersections in a given area. At the upper level, evacuees' total travel time was minimized and at the lower level, all traffic was assigned to the network with the traffic assignment-simulation software DynusT. A simulated annealing heuristic was used to solve the upper level problem. The entire method was applied to a real network to assess the impact of crossing elimination. Three scenarios were developed using different combinations of evacuee destination and departure time distributions. Results indicated that about 3-5 percent improvement in total evacuee travel time (9,700-11,200 hours for about 300,000 evacuees) was achieved in these scenarios. Availability of through movements and eliminating merging points were the two factors influencing the selection of modified intersection movement configurations.
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