Re: Cities Turning to Bicycles
Tim McNamara <timmcn@bitstream.net> wrote in message news:<m24ql7apmv.fsf@Stella-Blue.local>...
> Nate Nagel <njnagel@flycast.net> writes:
>
> > Tim McNamara wrote:
> >
> >> tetraethylleadREMOVETHIS@yahoo.com (Brent P) writes:
> >>
> >>>In article <m2is9ovqxc.fsf@Stella-Blue.local>, Tim McNamara wrote:
> >>>
> >>>
> >>>>Indeed, my review of some of the traffic management literature
> >>>>(e.g.,
> >>>>http://ops.fhwa.dot.gov/Travel/traff...k/chapter5.htm)
> >>>>suggests that traffic flow obeys the mathematics governing
> >>>>hydraulic flow, and that there is a maximum throughput in any
> >>>>hydraulic system before turbulence is created. Turbulence in turn
> >>>>creates drag and slows throughput dramatically. You can set the
> >>>>speed limit at the 85th percentile, but that will not "smooth out"
> >>>>traffic flow when there are just too many cars on the road at the
> >>>>same time- which is about 8 hours of every day in major urban
> >>>>areas.
> >>>
> >>>A smooth flow can sustain a higher throughput delaying the onset of
> >>>traffic jams and lessening how long they last.
> >> In an ideal world, sure. But you're dealing with a situation where
> >> by definition 85% of drivers are driving below the posted limit-
> >> which means the faster drivers are tailgating, trying to pass, and
> >> creating turbulence in the traffic flow. This rapidly becomes
> >> congestion. You're also dealing with drivers of radically
> >> different driving skills and driving preferences, so you get people
> >> driving 45 mph in the center lane on a road posted at 80 mph (in
> >> your ideal scenario of using the 85th percentile).
> >
> > Whoa! Hod it right there! That person should get a ticket - no
> > matter what the speed limit is. That's a completely separate issue,
> > and another pet peeve of mine.
>
> Well, then you're having to control people's behavior further by
> forcing the minimum speed limit higher than the current 45 mph posted
> on most interstate highways. Brent already complained vociferously
> about people telling him how to drive, but here we go again- this time
> on the slower rather than faster drivers.
Not necessarily. I don't have a problem with people driving 45 MPH on
the freeway, but I have a problem with them doing it in lanes other
than the right while everyone else is going a minimum of 70.
>
> > Slow traffic stays to the right, faster traffic passes to the left,
> > that way nobody gets "held up" until the highway is completely full.
> > that's the way it's *supposed* to work, anyway.
>
> Well, that's what *I* was taught in driver's ed lo those many many
> years ago. I see a *lot* of people, though driving 50 and slower in
> the middle lane.
As do I. But that doesn't change the fact that it's illegal in all
but a few states, so we don't even need to legislate anything. The
law just simply needs to be enforced... (not sure where you're
reading this from, but in RAD there is another thread going about the
utter and complete lack of enforcement of a supposedly new, stronger
KRETP law.)
> My mother- an alert and oriented 75 year old- claims
> she was taught that slow traffic should drive slow in the middle lane
> so that people can pass on either side. I've not had a lot of success
> convincing her this is a Bad Idea. Fortunately for all concerned she
> almost never drives on the highways.
Indeed, and I concur with your assessment.
>
> > The idea is to make it more like a laminar flow than a completely
> > turbulent one.
>
> If we can.
Sure we can. Other civilized countries seem to manage it fairly well,
and I have even experienced rare, blissful moments in this country
where I've found myself on a highway where everyone was KRETP. Just
for the record, I do tend to drive faster than the median speed of
traffic, but I'm rarely the *fastest* driver on the road, and yes, I
do do my part by yielding to faster traffic. Even when I'm not the
fastest driver on the road I still find things much less stressful
when I'm more able to accurately predict how those around me will
behave.
nate
