无需求预测的快速路紧急疏散最佳策略分析

An Optimal Strategy for Freeway Emergency Evacuation without Demand Estimation

以各种灾害所引起的紧急疏散为研究背景,针对一条快速路,设计一个不需要预测,自适应且鲁棒性强的高潜在风险优先疏散的疏散策略。首先给出了快速路疏散问题的数学化描述,计算出快速路系统疏散人数的上限和总疏散时间的下限。以典型的匝道-快速路合并为例,重点分析释放能力小于其下游关联路段通行能力的匝道疏散策略。通过定义潜在危险度,并利用该概念进而证明了新策略总是疏散出最大数量的居民且以最短时间完成疏散。算例分析结果表明新策略提高了紧急疏散中快速路的疏散效率。

An adaptive, non-anticipative, and robust emergency evacuation strategy giving priority to residents with high poten- tial risk is proposed for a freeway under various disasters. Firstly, the mathematical formulation of freeway evacuation problems is presented. The upper bound of evacuees evacuating through freeway system and the lower bound of total evacuation time can be deter- mined through the formulation. Secondly, based on a typical ramp-to-freeway merge, the evacuation strategy for the ramp with less capacity than its adjacent downstream freeway section is analyzed. Finally, the definition of the potential risk is given. With this con- cept, the effectiveness of the new strategy to maximize the total evacuees evacuated within the shortest time is proven. The numerical example illustrates that the new strategy has improved the efficiency of the freeway evacuation system.