Traffic design engineers were invited to a TRB webinar on Thursday, November 21, 2019, from 2:00 PM to 4:00 PM ET. The webinar provided an overview about using part-time signals to address peak hour flows at roundabouts. Many roundabouts built in the 1990s and 2000s are approaching their maximum design year volumes during peak hours. Part-time metering signals can equalize delays across roundabout approaches and ensure one approach does not dominate the roundabout during peak hours. The presenters also shared three case studies from across the country where early adopter agencies have successfully extended the design life of roundabouts during peak hours by using part time signalization.
This webinar was organized by the TRB Standing Committee on Roundabouts. It also referenced TRB reports about roundabouts, such as NCHRP Research Report 572 Roundabouts in the United States; NCHRP Research Report 672, Roundabouts: An Information Guide – Second Edition; and NCHRP Research Report 772, Evaluating the Performance of Corridors with Roundabouts.
The slides and a recording of the webinar are available.
Webinar Presenters
- Jeremy Kashman, City of Carmel
- Lisa Rene Schliperoort, Washington State Department of Transportation
- Ken Sides, Sam Schwartz Engineering
Moderated by: Gene Russell, Kansas State University
Webinar Outline
- Carmel, Indiana case study
- Washington State case study
- Florida case study
- Summary
- Question and answer session
The first 90 minutes of the webinar will be for presentations and the final 30 minutes will be reserved for audience questions.
Learning Objectives
At the end of this webinar, participants will be able to:
- Describe how the context of the area of the roundabout helps predict where flow patterns will change once a roundabout is built
- Identify specific installation parameters of the traffic signal hardware and its metering operation details
- Describe volume thresholds to be aware of when planning a roundabout for metering operations
- Describe the way roundabouts change the flow of traffic in an area based on the path of least resistance
Professional Development Hour Information
A certificate for 2 Professional Development Hours (PDHs) will be provided to Professional Engineers (PEs) who register and attend the webinar as an individual. For approved webinars, TRB’s webinar program awards Registered Continuing Education Provider (RCEP) Professional Development Hour (PDH) credits associated with participation only to the registered individual and not to other members of a group that view the webinar together. To receive PDH credits, please register as an individual and sign into the webinar from your personal computer. After doing this, you may join your group in a meeting room. To be eligible for the credits, individuals must remain signed in for the entire webinar, including for any question and answer session following the presentations.
In addition, advance registration is available until just before the webinar starts. Once the webinar starts, you will be unable to submit your registration. Individuals that are registered for a webinar but do not receive their confirmation emails due to their organization’s internal firewalls should contact the TRB Helpdesk (MyTRB@nas.edu) for assistance in signing in.
Individuals registered as Florida PEs are no longer required to email TRB with your license number to report your attendance. Instead, please use your certificate that TRB provides through RCEP.net as verification of your attendance to the Florida Board of Professional Engineers.
Please check with your licensing board to ensure that TRB webinar PDHs are approved by your board.
This Summary Last Modified On: 4/4/2022