TRANSPORTATION ACTIONS TO REDUCE HIGHWAY EVACUATION TIMES UNDER NATURAL DISASTERS

A computer simulation model was developed for the analysis and evaluation of evacuation plans for urban areas threatened by natural disasters. The model takes the network geometry, the natural disaster type and severity, and the socio-economic parameters of the threatened area as input, and produces as output network clearance times, best evacuation routes by zone, optimum shelter locations, sites of possible traffic bottlenecks, and proper traffic management strategies to alleviate them. It could be used as a tool to evaluate highway related measures for the ultimate goal of reducing the network clearance times.;The results indicated that in general the model is sensitive to population size, highway characteristics, available time for evacuation, traffic operational strategies, and natural disaster type.;The model was applied to the City of Virginia Beach as a case study, to determine the best evacuation plans under hurricane/flood conditions. The entire city was divided into four evacuation regions based on topography, land use, threatened areas, and highway network. Each region was simulated for evacuation under different hurricane/flood intensity levels and for various periods of the year. The network clearance times, the evacuation routes, the choice of shelters, and the transportation management strategies were determined for all the simulated scenarios. Also, the impact of future land-use development on the evacuation times were studied.