How To Build Roads To Control How Fast You Drive 801
An anonymous reader writes "They're the holy grail of transportation engineering: streets and highways specifically designed to encourage automobilists to drive less quickly, reducing the rates of passenger fatalities and generally encouraging a safer urban environment. And now new research shows that, if built right, they just might work. A new study out of the University of Connecticut suggests that minor reductions in vehicle speed are possible through changes in the street environment. Through the use of roadside parking, tighter building setbacks, and more commercial land uses, road designers can make drivers subconsciously drive more slowly." All of that is gonna work a lot better than my strategy of placing car-sized holes covered with twigs and branches randomly every half mile or so down the interstates.
Wow (Score:5, Informative)
Studies show that drivers adjust to the speed at which they feel safe, regardless of posted speed. So the only way to make them go slower is to make the road inherently *less* safe.
Also, similar studies show that driving about 5-10 mph faster than posted is actually about the safest speed you can go.
http://www.motorists.org/speedlimits/ [motorists.org]
There's also the argument that restricting the ability to drive quickly kills, as you slow emergency response vehicles as well. http://www.bromleytransport.org.uk/Ambulance_delays.htm [bromleytransport.org.uk]
All in all, one of the dumbest proposals I've ever heard. It seems that one of the easiest mistakes to make as an organization is to try to optimize for one contributing factor (speed) while ignoring the point of restricting that factor in the first place (reducing accidents).
Re:From the No Duh Dept. (Score:5, Informative)
The Germans and Dutch have been removing road signs and lights from roads for a few years now in experiments based on the theory that making roads more "dangerous" forces drivers to be more careful.
e.g. http://www.wired.com/wired/archive/12.12/traffic.html [wired.com]
From http://www.dw-world.de/dw/article/0,,2143663,00.html [dw-world.de], "When you don't exactly know who has right of way, you tend to seek eye contact with other road users,'' he said. ''You automatically reduce your speed, you have contact with other people and you take greater care."
Re:From the No Duh Dept. (Score:5, Informative)
http://www.car-accidents.com/pages/stats.html [car-accidents.com]
There were nearly 6,420,000 auto accidents in the United States in 2005. The financial cost of these crashes is more than 230 Billion dollars. 2.9 million people were injured and 42,636 people killed. About 115 people die every day in vehicle crashes in the United States -- one death every 13 minutes.
http://www.theclaimsconnection.co.uk/road-accident-claims1.html [theclaimsc...tion.co.uk]
The number of people killed in road accidents was down from 2,946 in 2007 to 2,538. In accidents reported to the police the number of people either killed or seriously injured stood at 28,572, a fall of 7%.
So roughly 42,000 deaths versus 2,500 deaths. 307m people in the US version 61m in the UK. Therefore the death rate per 1m people is 137 in the US versus 41 in the UK.
So, no, there aren't more here (where I assume you mean the UK).
Re:From the No Duh Dept. (Score:5, Informative)
Slowing also reduces pedestrian fatalities - at 20 mph, a collision with a pedestrian is unlikely to kill (around 10% chance, according to UK government figures), at 40 mph, it's overwhelmingly likely to kill (90% chance). At 30 mph, this is reduced to 50%. Kinetic energy increases at the square of speed, so small reductions in speed have a proportionately great reduction in collision energy.
Re:From the No Duh Dept. (Score:4, Informative)
British driving population:30,000,000
American driving population:193,552,000
0.00833 British deaths per 100 drivers
0.0217 American deaths per 100 drivers
(done for Anarki)
Re:Drive slower ... (Score:3, Informative)
Here, I’ll save you both the trouble.
MPH vs. MPG in top gear [metrompg.com] (scroll down to the non-hybrid examples)
Re:From the No Duh Dept. (Score:5, Informative)
It's gone further than that. I'm taking a motorcycle safety course with my wife. I have ridden for over 30 years, she is starting this year. They now teach you to assume that every car driver is intentionally going to kill you. we were told to assume that every car near you is being operated by a complete idiot that wants you dead.
And I agree with him, it's how I made it 30 years without an accident.
Re:From the No Duh Dept. (Score:5, Informative)
Ahem: http://en.wikipedia.org/wiki/List_of_OECD_countries_by_traffic-related_death_rate [wikipedia.org]
I think what you meant to ask for was "how many deaths per unit of vehicle distance travelled" since this controls not for how many drivers there are but for how much driving is actually going on. If you compare these numbers, you see that the US sees about 9 deaths per billion kilometers, and the UK sees 6.3 deaths. It's slightly more genuine and not nearly as 'shocking' (1.4x more vs 3.3x more fatalities) than the blanket deaths per person metric mentioned earlier. The UK sees fewer deaths overall in just about every measurable metric, however speculating on the actual causation is an exercise in futility left to the reader.
Re:The Numbers (Score:3, Informative)
Road Fatalities per Vehicle-Kilometers (or miles) is indeed how this statistic is normal measured. However, the results still favor the UK over the US (but stay the hell off the road in the United Arab Emirates).
Country Road Fatalities per Billion Vehicle-Kilometers
Sweden 5.9
UK 6.3
Australia 7.9
France 8.5
USA 9.0
Canada 9.2
NZ 10.1
Japan 10.3
South Korea 19.3
UAE 310
Source: List_of_countries_by_traffic-related_death_rate [wikipedia.org]
Re:Bullshit! (Score:5, Informative)
Re:From the No Duh Dept. (Score:5, Informative)
Actually, I do not believe that is the case. From what I had read and seen on documentaries on the Autobahn, it was constructed almost from the beginning for speed. It has banked turns to help keep you on the road at speed, and I believe the road materials are thicker and more greatly reinforced for strength, and better for tires to grip the road.
From what I'd read...it would cost a great deal more for the US to do their highways like this. That's why they weren't constructed to those specs originally. Unfortunately, with the economic problems we're in now...doubtful we'll ever upgrade or do new construction to specs that will allow for safely using them at significantly higher speeds.
I think the last show I saw on this, was on the History channel...maybe Modern Marvels? Interesting to say the least.
Re:Fuck this article (Score:3, Informative)
Than when?
Cars of today nearly universally have faster acceleration than cars of any previous decade. Power, torque, weight, gearing, and aerodynamics, as well as low internal resistance all contribute in various ways, depending on which specific cars you are comparing. But the trend is unmistakable: todays cars are much faster. Anecdote: My Minivan has more horsepower than my 1st generation BMW M5.
This is also false. The tires of today are absolutely amazing compared to rubber of just a few years ago. The suspensions of todays cars are considerably more advanced -- meaning they maintain effective tire adhesion in more sorts of circumstances. Todays cars control air flow much better than older cars -- it is uncommon for cars to have significant lift at highway speeds today, which was a serious safety hazard on older designs.
The brake system performance of the last 20 years are amazing compared to the pre-1980s stuff. The change away from asbestos drum linings to modern pad compounds and 4-wheel discs, and the introduction of ABS has really done wonders for stopping distances, fade resistance, and controllability in panic maneuvers.
Today I was driving on an empty stretch of curvy road in my prepared track car, a 1987 BMW 325. I was driving on bad street tires, but none the less, I checked my speeds at apex and before the final braking zone. My 2007 Audi station wagon shows a higher apex speed and a higher terminal speed through the same stretch of road, and it is still running my snow tires. It is about 800 lbs heavier and only has 30 more horse power, and unlike my much lighter BMW, the A4 gets 30mpg reliably on highways. That's fantastic performance out of a daily-driven family car.
The cars of today are truly amazing compared to those of even 20 years ago. I love older cars just as much as the next car guy, but they are uncompetitive, even against their newer, much heavier brethren. True, the margin of performance difference between new and old cars is often eclipsed by the breadth of driver-talent difference amongst the respective drivers, and so occasionally old cars win races against newer ones.
Also, the passive safety of todays vehicles is absolutely amazing: look at the technical data on iihs.org for details.
Drivers also have better opportunities to become better, safer drivers than ever before. The assertion that drivers aren't getting any better may or may not be true in the common case [i wasn't rating drivers 40 years ago], but the training available to drivers today who want to take it is fantastic.
I've personally taught teens, as part of the "Street Survival Program", car control and panic-avoidance techniques that you had to go to a racing instruction school to learn as recently as 10 years ago [which is where I learned them].
For those who wish to excel, now is a better time than ever to become a car pilot.
Re:Wow (Score:5, Informative)
the speed limits are generally set to the 85th percentile
Oh they are? And how do we know that?
If the speed limit is really set at the 85th percentile, only 15% of the vehicles will be traveling faster than the speed limit. Any average day on any average highway will suggest that this isn’t the case.
The only study I can find is dated from 1990 [ibiblio.org], but its findings are quite unsurprising to me:
On the average, 70% of drivers exceeded the speed limit: the speed limit was set at the 30th percentile, not the 85th.
"traffic calming measures" (Score:1, Informative)
The residents of this road fought for 20 years to get it closed off after new construction turned their quiet suburban neighborhood into a 75 mph on-ramp for Interstate 95.
Eventually they shifted tactics and got "traffic calming measures" installed.
http://maps.google.com/?ie=UTF8&t=h&layer=c&cbll=39.6814,-75.680048&panoid=ahLR2oaJziy1Hp2tOcx6NA&cbp=12,5.72,,0,5&ll=39.681314,-75.680033&spn=0,359.999032&z=20 [google.com]
Note the marks on the concrete. That curb was replaced last year because repeated impact of wheel rims at high speed pulverizes it after a while.
So, the normal speed on that road is now down to about 40 (speed limit is 25, of course, since it's residential) with occasional loud noises as someone tries to see what the functional limit is.
I think of it as a "stupid driver tax" and I heartily approve.
I bet if they installed large steel bollards in the center of the road, and moved them to a slightly different place every time they had to re-install one, they could get the traffic speed down to 25 mph. Basically by killing off all the people incapable of learning that compliance with the speed limit was no longer voluntary...