Phase II – Improved Work Zone Design Guidelines and Enhanced Model of Travel Delays in Work Zones

This project contains three major parts. In the first part a digital computer simulation model was developed with the aim to model the traffic through a freeway work zone situation. The model was based on the Arena simulation software and used cumulative interarrival times as the input. Its aim was to determine the traffic volumes through the work zone and the queue lengths in advance of lane restrictions. The program was designed to handle up to 15 miles in length, up to six lanes, and up to 20 entrance and exit ramps. The developed program has not been validated due to the lack of reliable field data and the program appears to produce unreasonably short queue lengths and low exit ramp traffic counts compared to the input traffic data for cases where the exit ramps are spaced closely together. In the second part a diversion analysis was performed to determine the effects of closed ramps. The work zone sites were assigned by Ohio Department of transportation and the diversion effects for these situations were in one case very minimal and in the other case as expected (traffic shifted to the next open exit ramp). In the third part guidelines for ramp management and ramp metering were established on a 24/7 basis giving special considerations to freeway mainline throughput and local traffic access to freeway.