Simulation Analysis of Truck Restricted and HOV Lanes

• Other Authors: Siuhi, Saidi (authoraut)
• Format: Others
• Language: English; English
• Published: Florida State University
• Subjects: Civil engineering; Environmental engineering
• Online Access: http://purl.flvc.org/fsu/fd/FSU_migr_etd-1693

Numerous studies have reported the efficacy of high occupancy vehicles (HOV) lane restriction and truck lane restriction implemented independently but the simultaneous use of both restrictions on an urban freeway corridor raises interesting questions related to the operational and safety implications of various confluence factors. This research study analyzed the operational and safety experience of an 83-mile corridor of Interstate 95 in South Florida that has both HOV and truck lane restrictions implemented individually and in combination. The results of a field-validated VISSIM simulation model emulating the current policy of restricting trucks from using the leftmost lane(s) in this corridor showed that high occupancy vehicles and automobiles gained significantly more travel time savings and speeds on the restricted lanes than on the general lanes. Also, vehicle queue lengths around critical merging and diverging areas increased significantly as the percentage of trucks increased imposing severe disruption on freeway traffic flow and vehicle backups spilling into the major intersecting arterial streets. The results indicated that during peak traffic conditions right lanes had high lane occupancy than left lanes whereas during off peak traffic conditions center lanes carried more vehicles per lane than the outermost lanes suggesting that congestion forces automobiles to use the left lanes. Furthermore, the results showed that the majority of lane changes occurred during peak traffic flow conditions—about twice that of off-peak—and appreciable speed differences existed between restricted and non-restricted lanes. The simulation results for off-peak traffic conditions did not show appreciable changes in traffic operating characteristics resulting from lane restriction strategies. Furthermore, simulation results showed that restricting trucks from using either center lane or the rightmost lane in lieu of the current policy of restricting trucks from using the leftmost lane(s) aggravate operational efficiency and safety. Based on these results, it can fairly be concluded that significant operational and safety benefits of combined implementation of HOV and truck lane restrictions on urban freeways accrue during congested traffic conditions rather than uncongested conditions when trucks are restricted from the leftmost lane(s). === A Thesis Submitted to the Department of Civil and Environmental Engineering in Partial Fulfillment of the Requirements for the Degree of Master of Science. === Fall Semester, 2006. === November 06, 2006. === Truck Lane restriction, HOV lane, VISIM Simulation === Includes bibliographical references. === Renatus N. Mussa, Professor Directing Thesis; John O. Sobanjo, Committee Member; Wei-Chou V. Ping, Committee Member.