Modern Roundabouts. Modern Roundabouts. Moderator: Gene Russell, P.E., Professor and Director Center for Transportation Research & Training, KSU Principle Investigator on 4 research projects on Modern Roundabouts. Kansas Dept. of Transportation
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Kansas Dept. of Transportation
Mack Blackwell National Rural Transportation Center
Insurance Institute for Highway Safety
Concerns / Questions
Whether or not these "Before" Concerns & Questions were answered?
Additional Concerns & Questions
First what they are NOT
No resemblance to Modern Roundabout
But opponents of Modern Roundabouts keep trying to compare them
Secondly, they are not small circles used primarily for neighborhood speed control
(Comment on your sheet if you have any problems with these "guidelines")
The answer is one of degrees
The entry radius is large so high speed entry is possible similar to the high speed circulating traffic Between entries and exits a considerable amount of weaving takes place. …
Capacity is determined by the weaving capacity of each weaving section. Weaving at (high) speed is dangerous and uncomfortable. US drivers I have met describe (large) traffic circles as a 'Free for all' after you enter.
2) High Traffic Volumes and Emergency Vehicles
3) Large Semi-Trucks
3) Football Traffic in Manhattan (predicted to back up 20 miles)
1) IIHS study showed 50 to 89% reduction in serious crashes at 24 sites where
2) Our KSU studies show that at the sites we have studied they are more efficient in terms of average delay, queue length and percent stopped than any other form of intersection traffic control, particularly 4-way stop control and traffic signals.
Special events traffic
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