ABSTRACT

Successful operation of ramp-metering needs to provide both an adequate queue storage space and a sufficient acceleration length at a metered on-ramp. This paper reviewed the existing methodologies and practices pertaining to queue storage and acceleration length design at metered on-ramps, and identified challenges that need to be solved during the metered on-ramp geometric design process. It was summarized that the development of metered on-ramp queue storage design guideline needs to consider the impact of on-ramp traffic flow arrival pattern on the actual queue storage needs at various metered on-ramp types. Meanwhile, considering the potential impact of ramp-metering on drivers’ acceleration behavior, it is necessary to develop dedicated acceleration lane length design standards for metered on-ramps based on field collected acceleration performance data. In addition, it is desirable to establish clear ramp geometric warrants to enhance the existing ramp-metering warrants presented in the MUTCD and local ramp meter design guidelines.

摘要

斜坡计量的成功运行需要在计量入口上提供足够的队列存储空间和足够的加速长度。本文回顾了有关在计量匝道上队列存储和加速长度设计的现有方法和实践，并确定了在计量匝道几何设计过程中需要解决的挑战。综上所述，计量入口队列存储设计指南的制定需要考虑入口流量流到达模式对各种计量入口类型的实际队列存储需求的影响。同时，考虑到坡度测量对驾驶员加速行为的潜在影响，有必要根据现场收集的加速性能数据为计量坡道制定专用的加速车道长度设计标准。此外，需要建立清晰的斜坡几何许可，以增强MUTCD和本地斜坡仪表设计指南中提出的现有斜坡计量许可。