Date of Award


Degree Name

Master of Science in Engineering


Civil and Construction Engineering

First Advisor

Dr. Valerian Kwigizile

Second Advisor

Dr. Jun-Seok Oh

Third Advisor

Dr. Pavel Ikonomov


Roundabouts, driving simulation, turbo roundabouts, multilane roundabouts, rotor turbo roundabout

Access Setting

Masters Thesis-Open Access


Roundabouts can be a solution to safety concerns present at other types of intersections. Recently in the United States, there has been an increase in conversion of problematic intersections to roundabouts to improve their safety. However, it is difficult to make these roundabouts, especially multi-lane roundabouts, safe to all ranges of users. Roundabout features such as advance warning and signage play an important role in determining driver performance as they navigate the roundabout.

This research is an effort to evaluate new and existing roundabout safety and operational features such as signs and pavement markings and how they influence performance of drivers at multi-lane roundabouts. It evaluates the two-lane roundabout and the rotor turbo roundabout as an alternative geometric design to a multi-lane roundabout. Virtual scenario simulation by use of a driving simulator is employed to probe driver response to a variety of roundabouts features.

The results indicate that lane keeping and speeding are still a problem in multi-lane roundabouts. The rotor turbo roundabout performs better in correctness of lane choice and navigation speed control. Yielding was not a significant problem in both kinds of roundabouts. Furthermore, it was found that roundabout signs and pavement markings used in the United States can be adopted for turbo roundabouts.