Outside of the box highway designs

[UNOstudent]

While browsing online, saw ways other places are dealing with traffic/road designs. Thought this was interesting and would share...

1.Zipper Lanes - a movable jersey barrier

Picture of it in use in Richmond, VA. http://www.roadstothefuture.com/Zipper_I95_JRB.html




Google Streetview of zipper lanes on Southeast Expressway in Boston
http://maps.google.com/?ie=UTF8&ll=42.2 ... .44,,0,8.7

Also mentioned in an article in Denver Post
http://www.denverpost.com/opinion/ci_14 ... source=pop


2.Center Turn Overpass - creating a raised intersection for left turns

The CTO separates turning traffic from through traffic and places it on a separate, independently timed level. Each level uses a 2-phase traffic signal as opposed to the conventional 4-phase traffic signal at a conventional intersection. The through traffic on the ground level sees 40% more green-time and the turning traffic above sees 75% more green time. In addition, the total cycle time is greatly reduced so traffic will see green lights twice as often.

Turning traffic runs up the ramp and stops at the traffic signal at the top. When traffic is light, the signal will be stop and go or demand-actuated. As traffic increases, the signals can be longer for more capacity. Since the traffic stops and turns at the top of the ramp, the ramp is a slow speed ramp as opposed to fly-overs. This means the ramps can be steeper and shorter than conventional overpasses - 65% shorter in fact. A conventional 6-lane overpass has over four times as much ramp cost as a CTO. Also, you decelerate uphill and accelerate downhill with a CTO so there is less noise, pollution and wear and tear on the vehicles.

http://web.archive.org/web/200105191956 ... rturn.com/






3.Continuous Flow Intersections

A Continuous Flow Intersection (CFI) allows drivers to turn left at the same time that others are turning left or going straight through. CFIs reduce congestion by providing more “green-light time” than traditional intersections. Traffic signals and street markings help drivers to navigate the intersection safely.

In use at 3500 South & Bangerter Highway in Salt Lake City

http://www.udot.utah.gov/wego/bangerter ... ments.html




4.Diverging Diamond Interchange

Illustrations of the first DDI in Springfield, MO

http://www.modot.org/springfield/major_ ... hotos.html

[StreetsOfOmaha]

Many of these intersections, especially the one in SLC, look like a pedestrian's nightmare.

[Choleric]

Or just use round-abouts like the rest of the sane world uses. Most effective intersection solution.

[almighty_tuna]

ok, i feel i gave this thread a chance before posting this. it was what i immediately thought of when I saw some of the above designs...

[riceweb]

The Center-Turning Overpass (CTO) could be really effective at both 90th and Dodge and 72nd and Dodge, though I can imagine there are some issues with the topography and right-of-way.

[mrsticka]

If you ask me, 14th and Superior here in Lincoln should've been changed into a CFI instead of a roundabout.