Guidelines for Activating and Deactivating Ramp Metering Signals During Off-peak Hours

Authors

John H. Kodi, Department of Civil and Environmental Engineering, Florida International UniversityFollow

Document Type

Dissertation

Degree

Doctor of Philosophy (PhD)

Major/Program

Civil Engineering

First Advisor's Name

Priyanka Alluri

First Advisor's Committee Title

Committee Chair

Second Advisor's Name

Albert Gan

Second Advisor's Committee Title

Committee member

Third Advisor's Name

Mohammed Hadi

Third Advisor's Committee Title

Committee member

Fourth Advisor's Name

Xia Jin

Fourth Advisor's Committee Title

Committee member

Fifth Advisor's Name

Wensong Wu

Fifth Advisor's Committee Title

Committee member

Sixth Advisor's Name

Thobias Sando

Sixth Advisor's Committee Title

Committee member

Keywords

Ramp metering signals, three-regime model, guidelines, activation, deactivation, off-peak hours

Date of Defense

3-28-2023

Abstract

Ramp metering is a traffic management strategy that uses signals installed at freeway on-ramps to manage traffic entering the mainline. Although ramp metering signals (RMSs) have been proven effective in reducing congestion during off-peak hours, few agencies use ramp metering during off-peak hours by activating RMSs based on the operator's judgment. However, this approach may not be the best practice to achieve optimal operating characteristics. This research used real-time traffic data to develop the guidelines for activating RMSs during off-peak hours. These guidelines were developed under normal traffic conditions, in response to incidents, and during rain. The three-regime model was used to calibrate the speed-occupancy relationship and estimate the breakpoint thresholds, which were used to recommend the activation guidelines for RMSs during off-peak hours.

The results indicate that for an incident occurred during daytime off-peak periods and results in lane blockage, the RMSs upstream of that incident may be activated when the average mainline speed drops below 45 mph and deactivated when the incident has been cleared and the average speed reaches 45 mph for a consistent 5-minute period. For nighttime off-peak periods, the RMSs upstream of that incident may be activated when the speed drops below 50 mph and deactivated when the incident has been cleared and the speed reaches 50 mph. For an incident occurred during daytime off-peak periods and does not require lane blockage, the RMSs upstream of that incident may be activated when the average speed drops below 50 mph and deactivated when the incident has been cleared and the speed reaches 50 mph.

The results also suggest that during daytime off-peak periods, RMSs may be activated in response to light rain when the average speed drops below 55 mph and deactivated when the rain stops and the speed reaches 55 mph. For moderate to heavy rain, the RMSs may be activated when the average speed drops below 50 mph and deactivated when the rain stops and the speed reaches 50 mph. The proposed guidelines will enable agencies to use RMSs to improve traffic operations in response to incidents and adverse weather during off-peak hours.

Identifier

FIDC011038

Recommended Citation

Kodi, John H., "Guidelines for Activating and Deactivating Ramp Metering Signals During Off-peak Hours" (2023). FIU Electronic Theses and Dissertations. 5284.
https://digitalcommons.fiu.edu/etd/5284