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#19179 of 21746 Re: Merging mania [andres3]
Aug 07, 2012 (10:46 am)
Last year I had a Kia driver get upset and start gesturing at me as we were merging, because I was pressuring him. I was driving the fintail, which is ~50 years old and has a 0-60 around 12 seconds floored - it's no muscle car. If I can get up to speed by the end of the ramp, he had no excuse - either trying to save a third of a cent worth of gas, or being too timid to get moving. Both have no place on a highway.
#19180 of 21746 Re: Roundabouts.... [andres3]
Aug 07, 2012 (10:58 am)
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.
Bicyclists Traveling through Roundabouts
Bicyclists can travel through a roundabout either as a vehicle (within the roundabout) or as a pedestrian (walking their bicycle). Some multi-lane roundabouts utilize an adjacent one-way trail where bicyclists approach the roundabout on-street, merge with the side trail via a ramp, travel around the roundabout on the trail, and then re-merge with the street via another ramp. This option presents some challenges with motor vehicles yielding at crossing points (similar to pedestrian issues described above). Notably, the reduced speeds of motor vehicles within the roundabout more closely match a bicyclist’s typical speed range (approximately 10 - 20 mph).
Emergency vehicles cannot speed through a roundabout like they can a signal light; they need to slow down and pass through the circle like regular traffic. Additionally, traffic signals offer the option for signal preemption to provide the green light to emergency vehicles; roundabouts require travelers to yield to emergency vehicles. Neither would the city fire vehicles negotiate the obstacles without considerable waste of time answering a fire or any emergency.
Illumination costs may be greater for a roundabout than a standard intersection as more lighting is typically required. More lighting may also be a concern of adjacent property owners, especially near residential areas
As with any new roadway configuration, highway maintenance staff will need to learn new snowplowing techniques
The construction of a roundabout to replace an existing traditional signalized intersection may result in the loss of some on-street parking if allowed near the former intersection.
The construction of a roundabout typically requires more right-of-way than a traditional intersection controlled by traffic signals or stops signs, which may increase the cost of a roundabout installation if right-of-way must be purchased.
Roundabouts may work in Europe where the cars and streets are much smaller, but over here it is not uncommon to see a 45’ motor coach pulling a toad, or a ¾ Ton pickup hauling a 5th wheel, or a tandem axle trailer with boat.
Roundabouts are not recommended, but wider intersections are because they are safer and handle the traffic with more efficiency.
#19181 of 21746 Re: Roundabouts.... [euphonium]
by steve_ HOST
Aug 07, 2012 (11:38 am)
Plenty of links say that roundabouts are safer for bikes and pedestrians. For example:
Some law firm, quoting the feds.
#19182 of 21746 Re: Merging mania [andres3]
Aug 07, 2012 (12:46 pm)
You haven't seen some of the junkyard dogs on the roads around here.
#19183 of 21746 Re: Roundabouts.... [euphonium]
Aug 07, 2012 (1:07 pm)
All excellent points about roundabouts.
Seen some Tour de France bicycle coverage on tv this year. They cover action with helicopters and camera persons on motorcycles.
There were numerous shots of roundabouts in France. Most of these seemed to be in sleepy, lightly populated semi-rural or small town areas.
#19184 of 21746 press request
by kirstie_h HOST
Aug 07, 2012 (1:21 pm)
If you live in or near Philly and have a 50+ mile commute (one way or RT), please email PRedmunds.com before Friday, August 17, 2012 to be interviewed by a reporter.
#19185 of 21746 Re: Roundabouts.... [xrunner2]
Aug 07, 2012 (4:59 pm)
Roundabouts work best where drivers are educated, aware, don't look at yapping/texting/eating while driving as a right, etc ...in other words, not in the USA.
#19186 of 21746 Re: Roundabouts.... [fintail]
by steve_ HOST
Aug 07, 2012 (6:13 pm)
Well, that kind of rules out all intersections here.
Biggest issue on getting more of them in the US is the higher cost of the right of way, especially for existing roads.
#19187 of 21746 Re: Merging mania [hammerhead]
Aug 08, 2012 (7:55 am)
Sounds like we need a vehicle code stating a 0-60 MPH time of 20 seconds or less, or your vehicle is not fit for the road and may not be registered legally.
Smog check places could test the acceleration is not deteriorating with age.
#19188 of 21746 Re: Merging mania [andres3]
Aug 08, 2012 (4:31 pm)
It depends on where you live. Around here, below is the common form of on/off-ramp.
You can tell how short the on/off ramp is by comparing it to the semi trying to merge onto the highway.