Conducted by: Tyler Womble

Roundabouts Vs. Traffic Signals

“A place where two or more roads meet, especially when at least one is a major highway”

Can be regulated by:• Stop Signs• Traffic Signals• Roundabouts

Intersections

http://forum.skyscraperpage.com/A roundabout located in Germany.

• Developed 1963 in England• 1990 first use in U.S. was Las Vegas• 3,700 throughout the U.S. (As of December

2013)• Despised throughout the U.S. by drivers

Roundabouts

http://www.gtcmpo.org/resources/topics/roundabouts.htm

• “The supervision of the movement of people, goods, or vehicles to ensure efficiency and safety”

• Developed in 1868 in England• First use in U.S. was 1910• Pedestrian crossing signs appeared in 1952

in New York

Traffic Signals

http://phys.org/news/

• Roundabouts Vs. Traffic Signals• Subcategories:• Construction• Safety• Efficiency• Design• Ease of Navigation• Maintenance Costs

Point of Disagreement

http://www.fcgov.com/engineering/vsi.php

Public Perception - Roundabouts

Roundabouts - Construction• Cheaper construction costs than signalized

intersection• Causes shut-down of entire intersection• Geometry is extremely important• Extremely low injury rate• Landscaping

http://www.signalscv.com/archives/107270/

• A little more expensive than roundabout• 1.4 million compared to 1.35 million• Intersection can remain open during final

stages• Electrical devices, sensors, and equipment

must be installed• Pedestrian stoplights

Signals - Construction

http://www.icollector.com/Give-Em-A-Brake-Sign_i14446930

• 2.6 times more likely to collide than at a signal

• Injury causing collisions same as signals• .04 pedestrian collisions per roundabout per

year• 1 cyclist collision every 14 years per

roundabout

Roundabouts - Safety

http://www.wpclipart.com/

• 3 times more likely to be killed than while at roundabout

• Injury causing collisions same as roundabouts

• .05-.08 pedestrian collisions per year• 1 cyclist collision every nine years per signal

Signals - Safety

http://accident.usattorneys.com/

• No form of control compared to signals• A new form of traffic control to U.S. drivers• 20% reduction in delays from signals• 56% reduction in vehicle stops

Roundabouts - Efficiency

http://www.reddit.com

• Green time is adjusted to fit flow of traffic• Easier for drivers to make maneuvers• Pedestrian crossing is adjusted easily• Requirements of drivers is easily identified

Signals - Efficiency

http://www.mylespaul.com

• Costs less than signals• Designs lacks• Signal timings• Electrical engineering• Signal design• Signal Timings

Roundabouts - Design

http://catimes.net/

• Warrants are easily listed and described• Geometry is easy to configure• Turn Lanes and protection• Dilemma zones must be avoided

Signals - Design

http://iamtraffic.org/

• Causes many collisions• Side swipes are frequent• Speed reduction• Drivers must be alert• Drivers must focus

Roundabouts - Navigation

Federal Highway Administration

• Drivers are comfortable with situation• Green means go, Red means stop• Yellow lights cause driver confusion

Signals - Navigation

http://blog.flair-systems.com/2010/05/intelligent-traffic-light-system.html

• Reduce maintenance costs • No hardware or electrical maintenance required

• Landscaping• Water Runoff

Roundabouts - Maintenance

http://www.virginiadot.org/

• Electrical Maintenance Required• Changing of signal times• Greater maintenance cost than roundabouts

Signals - Maintenance

http://www.gopixpic.com/

• Lost time in design• Driver Education• Construction Crew knowledge

Consequences

http://matherhs.org/

• More roundabouts to come!• More driver education• Better Results• Community Forums

Events

https://www.nevadadot.com/