Fundamentals of Roundabout Geometric Design


Roundabouts are becoming common in many parts of North America. Roundabout design is an iterative process which requires the balancing of safety, geometry and operational characteristics of the roundabout. Under certain conditions, roundabouts have been known to offer better safety benefits than other forms of intersections. In general, roundabouts operate safely when their geometric elements force traffic to enter and circulate at slow speeds causing the roundabout to have a small foot print. On the other hand, the roundabout must allow the passage of the largest vehicle expected to travel through the intersection. Striking the balance between the need to reduce speeds and maneuverability of large vehicles needs some trade-offs.

This online engineering course presents the fundamental geometric design principles based on NCHRP 672. The NCHRP 672 offers guidance on the basics of roundabout design where good experience and engineering judgement and application of best practices is required. As part of this webinar, you will learn:

  1. Basics of roundabouts
  • Familiarizing with the different types of roundabouts
  • Roundabout design workflow
  • Key roundabout geometric elements
  • Selecting the appropriate inscribed circle diameter
  • Designing the alignment of approaches and offset for deflection
  • Designing entry and exit curves, the central and splitter islands
  • Design vehicle turning checks
  • Other considerations
  • Fastest path, speed consistency and analysis
  • Determining the stopping and intersection sight distances
  1. Geometric design
  1. Safety considerations
  1. Apply this basic knowledge to a number case studies in live demo using AutoCAD and TORUS Roundabouts software.

Participants will need to review NCHRP 672 which is available for download here: The case studies and demo will be done using AutoCAD and TORUS Roundabouts.  Registered participants can request a trial copy of TORUS Roundabouts software by contacting the instructor directly.


Daniel Shihundu, P.Eng., MBA is the VP for Design Products at Transoft Solutions Inc, based in Vancouver, Canada. Daniel is passionate about transportation engineering software solutions and has with over 25 years of engineering, project management and client development experience in public and private projects within the consulting and construction industries. As a Project Manager, Design Lead and Engineer of Record, Daniel has an in-depth understanding of key aspects related to the planning, designing and construction of civil and transportation infrastructure projects. His extensive experience includes 20 years in the consulting sector in Canada and Africa in various roles specifically related to design, site safety, site supervision and project management of diverse projects from conception to completion.

There are currently no scheduled sections. Please contact the program coordinator to discuss options. 

 Alyssa Mercadante 352.273.1687

Credit Hours

3 Professional Development Hours (PDHs)

0.3 Continuing Education Credits (CEUs)