Modeling and Performance Assessment of a Transit-Based Evacuation Plan within a Contraflow Simulation Environment

TLDR

A bilevel optimization model selects waiting locations and shelters at bus stops and metro stations and dispatches rescue buses, while a contraflow simulation disperses interior and surrounding traffic. Simulation results show that adding contraflow operations to the transit-based evacuation plan reduces bottlenecks, improves system performance, and that higher transit usage further eases traffic dispersal.

Abstract

A bilevel optimization model is used to determine the waiting locations and corresponding shelters–in the case study, a combinatorial problem between bus stops and Metro stations–of a transit-based emergency evacuation plan and dispatch rescue buses toward the combinatorial locations. In additional, a contraflow simulation is elaborated to disperse the inside and ambient traffic of the target area. Results from the simulation can be used for modifying routing plans to avoid potential traffic bottlenecks. Findings indicate that the transit-based evacuation plan with the contraflow operations outperforms the same base plan without the contraflow operations. If more people select to evacuate via transit systems, the difficulties of dispersing traffic would be reduced and system performance remarkably improved.