Transportation Research Record: Journal of the Transportation Research Board ( IF 1.7 ) Pub Date : 2020-09-10 , DOI: 10.1177/0361198120943202 Hongmin “Tracy” Zhou 1 , Magdy Kozman 2
Traffic in Houston, U.S., has continued growing over the past decade. The Houston District of the Texas Department of Transportation (TxDOT) recently began a pilot study to evaluate a dynamic ramp metering system. The project is aimed to convert ramp metering from local control to system-wide dynamic operation. In Phase I of the project, major control parameters and different metering strategies were tested and evaluated in simulation and field settings for a study corridor installed with six ramp meters. The study identified a base metering plan that overall worked well for sites without restrictive queue conditions. This base plan was that average speed of 50 mph or lower in the right-most two mainlanes will call for metering at a constant metering rate of 850 vehicles per hour for at least 4 min, and that queue occupancy of 50% or higher will call for meter shutdown for at least 1 min. Ramp metering coordinated with the downstream intersection performed well by accommodating diverted traffic caused by ramp metering. When operating ramp meters in a group, metering the immediately upstream meter performed best compared with metering further upstream meters. It is evident that ramp metering caused traffic diversion to the frontage road and also caused reduced queue-jumping behaviors on the frontage road at ramp meters with an immediately upstream exit ramp. The coordinated ramp metering strategy can potentially generate a benefit/cost ratio of 117:1 compared with local metering in the District.
中文翻译:
休斯顿动态斜坡计量先导研究第一阶段的结果
在过去的十年中,美国休斯敦的流量持续增长。得克萨斯州交通局的休斯顿区(TxDOT)最近开始了一项初步研究,以评估动态坡道计量系统。该项目旨在将斜坡计量从本地控制转换为系统范围的动态运行。在该项目的第一阶段,在安装了六个坡度计的研究走廊的模拟和现场设置中,测试并评估了主要控制参数和不同的计量策略。该研究确定了一个基本的计量计划,该计划总体上适用于没有限制性队列条件的站点。此基本计划是,最右边的两个主干道的平均速度为50 mph或更低,将要求以每小时850辆车的恒定计量速度计量至少4分钟,并且该队列占用率达到50%或更高将要求电表关闭至少1分钟。通过适应由坡道计量导致的转向交通,坡道计量与下游交叉口协调良好。与成组的上游仪表相比,对一组斜坡仪表进行操作时,对紧邻的上游仪表进行计量的效果最佳。明显的是,匝道计费导致流量转移到临街,并且还导致了在匝道流量计处的临街上具有直接上游出口匝道的排队跳跃行为减少。与区域内的本地计量相比,协调的匝道计量策略可以潜在地产生117:1的收益/成本比。通过适应由坡道计量导致的转向交通,坡道计量与下游交叉口协调良好。与成组的上游仪表相比,对一组斜坡仪表进行操作时,对紧邻的上游仪表进行计量的效果最佳。明显的是,匝道计费导致流量转移到临街,并且还导致在匝道流量计处的临行道路上具有紧靠上游出口匝道的排队跳跃行为减少。与区域内的本地计量相比,协调的匝道计量策略可以潜在地产生117:1的收益/成本比。通过适应由坡道计量导致的转向交通,坡道计量与下游交叉口协调良好。与成组的上游仪表相比,对一组斜坡仪表进行操作时,对紧邻的上游仪表进行计量的效果最佳。明显的是,匝道计费导致流量转移到临街,并且还导致在匝道流量计处的临行道路上具有紧靠上游出口匝道的排队跳跃行为减少。与区域内的本地计量相比,协调的匝道计量策略可以潜在地产生117:1的收益/成本比。明显的是,匝道计费导致流量转移到临街,并且还导致在匝道流量计处的临行道路上具有紧靠上游出口匝道的排队跳跃行为减少。与区域内的本地计量相比,协调的匝道计量策略可以潜在地产生117:1的收益/成本比。明显的是,匝道计费导致流量转移到临街,并且还导致了在匝道流量计处的临行道路上具有紧邻上游出口匝道的排队跳跃行为的减少。与区域内的本地计量相比,协调的匝道计量策略可以潜在地产生117:1的收益/成本比。