[gps-talkusers] Re: What?
- From: Janet Barlow <jmbarlow@xxxxxxxxxxxxxx>
- To: gps-talkusers@xxxxxxxxxxxxx, <gps-talkusers@xxxxxxxxxxxxx>
- Date: Mon, 13 Dec 2004 17:11:14 -0500
Traffic engineers in the US and other countries will tell you that a
traffic circle or a rotary is not a "modern roundabout". There are some
differences, mainly in the design of the intersections, pedestrian
crosswalks, and the movement of traffic.
From http://www.gtcmpo.org/Roundabouts/Roundabouts.htm#What_is_a_Roundabout
"What is a Roundabout?
A roundabout is a circular intersection joining two or more streets. The
streets that connect to a roundabout feed traffic into a "circulatory
roadway" that surrounds a central island. Traffic on the circulatory
roadway flows in a counterclockwise direction. All turns and lane changes
that drivers make when entering, while within, and when leaving a
roundabout are right turns, which adds both to the ease, efficiency, and
safety with which drivers pass through roundabouts.
How Does a Roundabout Work?
As a driver approaches the entrance to a roundabout, he/she slows down and,
if possible, merges with traffic on the circulatory roadway (the
roundabout) without stopping. A Yield Sign controls each entrance into a
roundabout. There is no need to stop completely if space is available
within the roundabout to enter. Once in the roundabout, drivers move
slowly with traffic around the central island. Speeds of 10 to 15 mph are
typical for small roundabouts and 20 to 30 mph for larger
roundabouts. When a driver approaches his/her desired exit, they use their
right turn signal and make the right turn needed to leave the roundabout
......Pedestrians Traveling through Roundabouts
Since traffic is continually flowing in and out of the roundabout and is
not controlled by a signal, there is no time when a pedestrian can be
reasonably certain that a vehicle will not pass over the
crosswalk. Roundabouts can also be difficult for visually impaired
pedestrians to determine the moment when it is safe to cross as many
utilize traffic sounds to determine when a roadway is clear. Additionally,
the route pedestrians must take around a roundabout is longer than the
route they would take to walk through many signalized intersections.
Note that these descriptions do not really describe the pedestrian
crossings which is probably of primary interest to this group. The
pedestrian crossing are typically marked on the entry and exit lanes about
two cars lengths before the circle, so a pedestrian who is continuing
straight, with the parallel street on his left, has to curve around to the
right, locate the crossing point, turn left and cross the cross street,
turn left, then curve back around to the right to continue along the road
they were walking along. And while cars are supposed to yield to
pedestrians in crosswalks, they rarely do and the traffic noise in the
circle can mask the sounds of traffic approaching the crosswalk. A
difficult to impossible safe crossing at a busy roundabout, but maybe a
manageable one at a small less busy roundabout.
Janet
At 02:30 PM 12/13/2004, donald.goosens wrote:
>Please excuse my ignorance --What are roundabouts, what do they do, and
>how do they work?
>Donald
Janet M. Barlow, COMS
Certified Orientation and Mobility Specialist
jmbarlow@xxxxxxxxxxxxxx
770-317-0611
Atlanta, GA
-------------------
The information transmitted is intended only for the person or entity to
which it is addressed and may contain confidential and/or privileged
material. Any review, retransmission, dissemination or other use of, or
taking of any action in reliance upon this information by persons or
entities other than the intended recipient is prohibited. If you received
this in error, please contact the sender and delete the material from any
computer.
Other related posts: