Roundabout Safety and Operations

Granting Agency: Wisconsin Department of Transportation

Researchers: David Noyce (PI), Andrea Bill, Madhav Chitturi

Primary Project Objectives

The objective of this research is to examine roundabouts that did not perform as expected to see if any further improvements can be made from the original study. Additionally a safety evaluation was performed on six additional roundabouts plus all roundabouts built in 2008 that were not part of the original study. By analyzing these accidents in terms of geometrics, signing/marking, and education we determine what the best steps for improvements are.

Aerial view of roundabout

In an effort to aid the Wisconsin Department of Transportation improve roundabouts (RABs) throughout the state, the TOPS Lab identified RABs that didn’t perform as expected during the first phase of this project. By creating crash diagrams and surveying the regions locals we are able to help determine/identify concerns such as signing or markings. Additionally six RABs were examined which were not included in the original study. For these RABs the crash frequency is calculated if the new intersection was a signal or stop controlled. The final task during Phase Two was adding all RABs built in 2008 into the dataset and determining long term crash trends.
Another aerial of a roundabout