Performance-Based Traffic Planning with Roundabouts

MTJ Engineering is a leader in performance-based traffic planning with roundabouts.

MTJ works as a subject area expert at the interface of traffic planning, analysis and geometric design on project teams aimed at maximizing community benefits and delivering successful, well-received roundabouts across North America.

Existing Roadway Planning Policies

• Existing traffic and roadway planning policiesand standards are predominantly based on signalized intersections.
• Roadway capacity/cross-section is dictated by signal lane saturation rates
• Access control is based on the functional areas of signals
• Progression often dictates intersection spacing
• The differing performance characteristics of roundabouts affect these planning standards

Performance-based design focuses on performance improvements that benefit both project and system needs.

MTJ conducts analysis and design for roundabout projects with a performance-based planning approach, utilizing the unique operational attributes of roundabouts to achieve project objectives while minimizing impacts and costs.

This enables us to arrive at solutions not possible with standard roadway planning approaches. MTJ’s designs are anchored in human factors research and roadway, traffic, and roundabout-specific safety principles.

Performance-based Planning Components Include:

1. Roadway Cross-Sections

• Reduced roadway/structure widening
• Flared entry design provides capacity improvements
• Capacity improvements at intersections

2. Intersection Spacing Versatility

• Progression not necessary with roundabouts
• Design customized for each context and operational objectives
• Lane continuity

3. Access Management / Different Functional Areas

• Driveway access spacing flexibility
• U-turn, left turn, right turn all have same priority as through movement
• Slower speed facilitates improved ingress/egress decision-making