Throughout Florida, there are several freeway interchanges where queues on the off-ramps spill back onto the freeway mainline. This creates a potentially hazardous condition where high-speed traffic on the freeway suddenly comes up on traffic stopped and queued from the off-ramp. This situation leads to a potential for increased high-speed rear-end collisions on the mainline as well as an increased probability for sideswipe crashes when vehicles suddenly change lanes to avoid hitting the back of the queue. In many cases, the problem is that the congested freeway is dumping a heavy traffic load on an already congested arterial roadway. At many of these locations, signalized intersections closely spaced to the freeway off-ramp make the bad situation worse. Typically, all that we can do is to alert motorists via dynamic message signs (if available) of upcoming congestion. The objective of this project is to develop a toolbox of potential countermeasures for reducing queues at off-ramps. (Author/publisher)
Abstract