Slip ramp spacing design for truck only lanes using microscopic simulation

This research work proposes recommendations for slip ramp spacing between the TOLs and the general GPLs along Missouri rural interstate highways using a microscopic simulation model, VISSIM. Simulation of peak period rural traffic conditions indicated that heavy vehicle speeds were directly proportional to the lengths of the merge, diverge, and link sections. The proposed design recommendations for slip ramp spacing are based on the results of these section lengths. Design of experiments was carried out using a central composite design. As the slip ramp spacing depended heavily on the lane change behavior of drivers, a sensitivity analysis was performed of the main lane change parameter in VISSIM that analyzed its effect on the speed flow characteristics of heavy vehicles. This work provides practitioners and state Departments of Transportation (DOTs) with design recommendations for slip ramp spacing and lengths of merge, link, and diverge for the corridors of the future project --Abstract, page iv