Integrated Reconfiguration of Both Supply and Demand for Evacuation Planning

Abstract

Evacuation planning is a challenging task due to the suddenly increased large transportation demand in emergency situations. The imbalance between demand and supply of transportation systems is the key problem during evacuation. Existing literature has tried to increase the traffic capacity but not to reduce the demand. This paper proposes a novel integrated reconfiguration strategy that reconfigures both the supply and demand sides of transportation systems; in particular, the evacuation demand is reconfigured using a heterogeneous fleet of vehicles and the traffic capacity supply is reconfigured through a heterogeneous contraflow technique. Four strategies, i.e., do-nothing, supply reconfiguration, demand reconfiguration, and integrated reconfiguration, are compared. The general integrated strategy is formulated as a bi-level programming model which is solved by a two-layer algorithm composed of the tabu search (TS) and priority-based minimum cost flow (P-MCF) algorithm. The experimental results justify the effectiveness of the reconfiguration method and show that the integrated reconfiguration strategy performs best under any circumstance while the ranking of the other three strategies depends on the number of vehicles and evacuees.