The Federal Highway Administration (FHWA) Alternate Route Handbook proposes guidance to identify alternate routes during planned and unplanned road closures. A challenge with this process is the lack of traffic data available to decision-makers. High volume corridors experiencing unplanned closures can provide a rich case history by systematically collecting connected vehicle (CV) data during such incidents. CV data provide the ability to directly measure actual diversion routes and travel times during an ongoing or historical incident. This paper presents methodologies to systematically analyze diversion data to identify the most common alternate route choices and impacted interstate exits, valuable information for public safety and transportation agencies to evaluate the surrounding road network’s resiliency in accommodating diverting traffic. Agencies can use this information to proactively deploy resources (officers, signs, barricades) at critical locations during future closures. The scalability of this methodology is demonstrated by evaluating 12 additional cases to assess diversion rates found to be in the range of 58% to 93% for total closures exceeding five hours. The paper concludes by recommending agencies apply these methodologies to develop data-driven diversion strategies on critical routes coupled with real-time CV monitoring in dispatch centers to provide agile adjustment of resources along diversion routes.

中文翻译：

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计划和非计划封路期间的路线选择分析


联邦公路管理局 (FHWA) 备用路线手册提出了在计划内和计划外封路期间确定备用路线的指南。此过程的一个挑战是决策者缺乏可用的交通数据。经历意外关闭的大量走廊可以通过在此类事件期间系统地收集联网车辆 (CV) 数据来提供丰富的案例历史。 CV 数据能够直接测量当前或历史事件期间的实际改道路线和行驶时间。本文提出了系统分析分流数据的方法，以确定最常见的替代路线选择和受影响的州际出口，为公共安全和交通机构评估周围道路网络在适应分流交通方面的弹性提供了宝贵的信息。各机构可以利用这些信息在未来关闭期间主动在关键地点部署资源（人员、标志、路障）。该方法的可扩展性通过评估另外 12 个案例来评估，发现总关闭时间超过 5 小时的转移率在 58% 至 93% 范围内，从而证明了该方法的可扩展性。本文最后建议机构应用这些方法在关键路线上制定数据驱动的分流策略，并结合调度中心的实时 CV 监控，以灵活调整分流路线沿线的资源。