Using Archived Data to Measure Operational Benefits of a System-Wide Adaptive Ramp Metering (SWARM) System: Appendix Online 6: OR-217 NB Time-Space Speed Contour Plots with Meter Activations

US Transportation Collection2008PDFStatistical ReportPortland State University. Department of Civil & Environmental EngineeringOregon Transportation Research and Education ConsortiumOregon Transportation Research and Education ConsortiumOregonUnited StatesTraffic speedGraphsData plottersRamp meteringHighwaysOperations and Traffic ManagementI73: Traffic ControlA System-Wide Adaptive Ramp Metering (SWARM) system has been implemented in the Portland, Oregon metropolitan area, replacing the previous pre-timed ramp-metering system that had been in operation since 1981. SWARM has been deployed on six major corridors and operates during the morning and afternoon peak hours. This report presents results of a \u201cbefore\u201d and \u201cafter\u201d evaluation of the performance of two freeway corridors as part of ongoing efforts to measure the benefits of the new SWARM system, as compared to the pre-timed system. The study benefited from using the existing regional data, surveillance and communications infrastructure in addition to a regional data archive system. The evaluation revealed that the operation of the SWARM system, as currently configured in the Portland metropolitan region, produced mixed results when comparing the selected performance metrics to pre-timed operation.125