The main objective of this study is to evaluate the safety and operational impacts of an innovative infrastructure solution for safe and efficient integration of Automated Vehicle (AV) as an emerging technology into an existing transportation system. Filling the gap in the limited research on the effect of AV technology on infrastructure standards, this study investigates implications of adding a narrow reversible AV-exclusive lane to the existing configuration of I-15 expressway in San Diego, resulting in a 9 ft AV reversible lane and, in both directions, two 12-feet lanes for HOV and FasTrak vehicles. Given the difference between the operation of AVs and human-driven vehicles and reliance of AVs on sensors as opposed to human capabilities, the question is should we provide narrower AV-exclusive roadways assuming AVs are more precise in lateral and longitudinal lane keeping behaviour? To accomplish the goal of the project, a historical crash data analysis and a traffic simulation analysis were conducted. Crash data analysis revealed that unsafe speed, improper turning, and unsafe lane change are the most recurring primary collision factors on I-15 ELs. AVs’ automated longitudinal and lateral control systems could potentially reduce these types of collisions on an AV-exclusive lane with proper infrastructure features for AV sensor operation (e.g., distinct lane marking). Microsimulation findings indicated an AV-exclusive lane may increase traffic flow and density by up to 14% and 24%, respectively. It also showed that average speed is reduced. However, this could lead to the speed differential increase between the exclusive lane and adjacent lane requiring careful consideration if additional treatments or barriers are needed. The results of this study contribute to infrastructure adaptation to AV technology and future AV-exclusive lanes implementations.

中文翻译：

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15号州际高速公路专用车道上狭窄的自动车辆专用车道的含义

这项研究的主要目的是评估创新基础设施解决方案的安全性和运营影响，该解决方案可将自动驾驶汽车（AV）作为一种新兴技术安全有效地集成到现有运输系统中。为了填补有关视音频技术对基础设施标准的影响的有限研究的空白，本研究调查了在圣地亚哥的I-15高速公路的现有配置中添加狭窄的可逆视音频专用车道的含义，从而实现了9英尺视音频可逆车道和两个方向的HOV和FasTrak车辆的12英尺车道。考虑到自动驾驶汽车和人类驾驶车辆的操作之间的区别以及自动驾驶汽车对传感器的依赖而不是人类的能力，问题是，如果在横向和纵向车道保持行为中AV更加精确，我们是否应该提供更狭窄的AV专用道路？为了实现该项目的目标，进行了历史碰撞数据分析和交通模拟分析。碰撞数据分析表明，不安全的速度，不正确的转弯和不安全的车道变更是I-15 EL上最经常发生的主要碰撞因素。视障者的自动纵向和横向控制系统可能会通过针对视障传感器运行的适当基础设施功能（例如，明显的车道标志）来减少在视障者专有的车道上发生的此类碰撞。微观模拟结果表明，AV专用车道可能分别将交通流量和密度提高多达14％和24％。这也表明平均速度降低了。然而，这可能会导致专用车道和相邻车道之间的速度差异增大，如果需要其他处理或障碍，则需要仔细考虑。这项研究的结果有助于基础设施适应视音频技术和未来视音频专用通道的实施。