M.S.

Most vehicular tunnels, due to their restrictive and confined environment require continuous traffic surveillance and control. This is achieved by a variety of systems like closed circuit TV monitoring, personnel stationed in the tunnel, overheight & speed detectors and others. Traffic flow data were obtained from the Interstate 64(I -64) Hampton Roads Bridge-Tunnel. The data were analyzed and conclusions were drawn about traffic flow behavior at the different tunnel sections. During the operation of a tunnel, capacity reductions are often experienced due to temporary lane closures. These could result from incidences occurring in the tunnel area or due to regular maintenance activities. This work concentrates on the former case. A microcomputer model called Queue and User Cost Evaluation of Work Zones(QUEWZ) was employed in studying lane closure scenarios for the Virginia Tidewater Area Tunnels. In case of significant capacity reductions or complete blockages of directions of travel, it is desired to know beforehand the impact expected on the surrounding network. Traffic management actions like rerouting policies could be implemented and thus alleviate the problem. MASSVAC2, a computer simulation model for mass evacuation under emergency conditions was employed for analyzing different traffic management scenarios. / M.S.