A Dynamic Merge Metering-Based Unconventional Alternative to Traffic Control at Highway Bottlenecks

This paper presents an unconventional alternative to integrating the dynamic late merge with a merge metering at the downstream taper area of a physical bottleneck (e.g., work zone), termed as dynamic merge metering traffic control system for work zones (DMM-Tracs). The architecture and communication system for the DMM-Tracs, including system components, communication technologies and operation mechanism, are introduced. With this system, the merge metering control will be activated depending on the volume detected at an upstream location of the work zone. If the thresholds of control parameters are met, a merge metering signal installed at the taper area will be activated and approaching vehicles will be instructed in the advance areas of the work zone. To reduce forced merges and potentials of merge conflicts, the control scheme will adjusted on the realtime basis depending on the detected traffic conditions. The delay penalty is distributed equally in all lanes. This potentially increases the efficiency with which the traffic is discharged into the open lane inside the work zone. A portable controller is the "brain" of the DMM-Tracs System to receive data from detectors, to process the data, and to control the merge metering signal via wireless communications. The efficacy of the DMM-Tracs is evaluated via a micro-simulation test bed with VISSIM. Meanwhile, the volume threshold values are also determined via the simulation.