June 23, 2020
This is a free virtual series that will begin at:
June 23 at 1:00 pm
June 30 at 1:00 pm
July 7 at 1:00 pm
All times are Central Time Zone.
Details to access the Webex webinar will be emailed along with a confirmation after you register. Only one link will be provided and that is all that is necessary to access the webinar each week.
Iowa LTAP is pleased to offer a series of Roundabout Town Halls presented and moderated by roundabout expert Hillary Isebrands of the Federal Highway Administration. These webinars will cover various roundabout topics, with approximately 20 minutes of presentation followed by question and answer sessions in a town hall format.
This will be a three-part event (registration will cover all three weeks of the series), taking place on the following dates:
June 23 from 1:00 pm – 2:00 pm
June 30 from 1:00 pm – 2:00 pm
July 7 from 1:00 pm – 2:00 pm
Topics to be covered include:
June 23 – General overview
- High level overview of design documents, i.e. NCHRP Report 672.
- Process used to select roundabouts as the design of choice for the intersections.
- Different types of roundabouts, i.e. mini-roundabouts, full size roundabouts, compact roundabouts, retrofitting roundabouts to existing intersection pavement.
June 30 – Operations
- High level overview of the capacity of roundabouts, options for conducting traffic analysis of roundabouts, one-lane vs two-lane roundabouts, etc.
- Performance checks for roundabout design, i.e. fastest path, design vehicle, natural path, sight distance, etc.
July 7 – Design
- Design of the roundabout entries/exits.
- How to determine the size of the Inscribed Circle Diameter (ICD), size of circle.
- Pedestrian accessibility (NCHRP 834) and bicycle treatments.
- What are the design/staging considerations (grades, roundabout location, staging) for if a roundabout needs to be completed while maintaining traffic? Or is it not possible or highly not recommended?
Note, the full National Highway Institute roundabout training will still be offered later this year.
About the presenter/moderator: Hillary Isebrands has served in the transportation profession for over 24 years. She focuses her work on improving the design and safety of our nation’s roadways by providing technical assistance, training and technology deployment of proven safety countermeasures. Hillary is Senior Roadway Safety Engineer and Team Leader with the FHWA, Resource Center, Safety and Design National Technical Service Team. She specializes in roundabouts and local and rural roadways. Hillary is a Professional Engineer, a National Highway Institute Certified Instructor and has her BS (’97), MS (’04) and PhD (’11) in Civil Engineering from Iowa State University. Hillary is the Secretary for the TRB Committee on Roundabouts, past Member of the TRB Committee on Geometric Design, and past Chair of the ITE Roundabout Task Force.