Design Issues Related to Road Tunnels

This report is the first phase of a multi-year, ongoing research effort to identify and evaluate the impact of roadway design elements on driver behavior. The focus of this work is on road tunnels, but similar questions apply in other roadway environments.

The organization of this document reflects the research process employed in this project. First, the background is established indicating the increasing use of road tunnels to solve many planning problems. The next section identifies two groups of potential problems related to road tunnel design from the driver's point of view-those related to the general image of the tunnel, and those related to traffic flow and safety. Then, a case study of the proposed Stockholm tunnel system illustrates some real design responses to tunnel design problems. Based on these strategies and actual design approaches, a list of research questions is compiled. Finally, the two-phase research approach for this project is described. In phase one, computer models are developed and observations are made based on drive through simulations. In the second phase, subjects will be tested using the driving simulations at the Human Factors Research Lab to determine how their driving behavior is influenced by design elements.