A Bi‐Level Model for Planning Signalized and Uninterrupted Flow Intersections in an Evacuation Network

Abstract

The problem to be addressed in this paper is the lack of an advanced model in the literature to locate the optimal set of intersections in the evacuation network for implementing uninterrupted flow and signal control strategies, respectively, which can yield the maximum evacuation operational efficiency and the best use of available budgets. An optimization model, proposed in response to such needs, contributes to addressing the following critical questions that have long challenged transportation authorities during emergency planning, namely: given the topology of an evacuation network, evacuation demand distribution, and a limited budget, (1) how many intersections should be implemented with the signals and uninterrupted flow strategies; (2) what are their most appropriate locations; and (3) how should turning restriction plans be properly designed for those uninterrupted flow intersections? The proposed model features a bi‐level framework. The upper level determines the best locations for uninterrupted flow and signalized intersections as well as the corresponding turning restriction plans by minimizing the total evacuation time, while the lower level handles routing assignments of evacuation traffic based on the stochastic user equilibrium (SUE) principle. The proposed model is solved by a genetic algorithm (GA) ‐based heuristic. Extensive analyses under various evacuation demand and budget levels have indicated that the location selection of uninterrupted flow and signalized intersections plays a key role in emergency traffic management. The proposed model substantially outperforms existing practices in prioritizing limited resources to the most appropriate control points by significantly reducing the total evacuation time (up to 39%).

Dual effects of guide-based guidance on pedestrian evacuation

“…It is worth noting that, in a broad sense, the adverse effect found in this study is somewhat similar with the "faster-is-slower" effect [2]. Both of them reveal that, in some situations, the action and measure that seems to be positive to the pedestrian evacuation may conversely cause a negative result.…”

“…The macroscopic pedestrian evacuation guidance studies represent evacuations as optimization models on road networks. Guidance strategies, including the road design on evacuation networks [1], the location of intersections, signal controls and turning restrictions [2][3][4][5], lane control [6] and route guidance information [7] were addressed through solving these optimization models.…”

A Cell‐Based Distributed‐Coordinated Approach for Network‐Level Signal Timing Optimization

“…He found optimal signal timing parameters to minimize travel delay in an isolated intersection (Webster, ). Since then, many developments in the field of signal timing optimization (e.g., Liu and Luo, ; Haijema and Hendrix, ; Varia and Dhingra, ; Chai and Wong, ; Zhao et al., ; Teklu et al., ; Putha et al., ; and Sun et al., ) especially at network level have been conducted. Furthermore, researchers have paid attention to other methods of traffic congestion management including: ramp metering (Jiang and Chung, ), traffic assignment (Levin et al., ; Sancho et al., ; Zhou et al., ), and variable speed limit control (Li et al., ). …”

Calibrating Rail Transit Assignment Models with Genetic Algorithm and Automated Fare Collection Data

“…The use of GA to solve some complex optimization problems was first proposed in the middle of the 1970s (Holland, ). Since 1993, GA has been used as an effective optimization tool for highly nonlinear optimization problems in various areas such as engineering design optimization (Adeli and Cheng, , ; Chau and Albermani, ; Adeli and Sarma, ; Chabuk et al., ; Sgambi et al., ; Hejazi et al., ), construction resource utilization (Cheng and Yan, ), highway alignment optimization (Kang et al., ), wastewater system planning (Zeferino et al., ; Jafarkhani and Masri, ), structural control (Jiang and Adeli, ), environmental engineering (Martínez‐Ballesteros et al., ), condition monitoring (Baraldi et al., ), image processing (Carro‐Calvo et al., ; Pedrino et al., ), forecasting of freeway accident duration times (Lee and Wei, ), traffic signal coordination (Putha et al., ), evacuation network planning (Liu and Luo, ), and system identification of novel materials (Fuggini et al., ). However, there is not yet any application in the calibrations of URT assignment models.…”