Some observations on speed-flow and flow-occupancy relationships under congested conditions

There is a need for a better understanding of freeway operations under congested conditions. Not only are major freeways in many cities congested several hours a day, but intelligent vehicle-highway system programs to be able to function effectively under all conditions, aggregate traffic behavior under all conditions needs to be accurately modeled. Three models for congested flow-occupancy data have been put forward in the past. Using data …