[Vwdiesel] Per mile costs

[James Hansen]

Not that I'm doubting your opinion Val, I know you are a pretty thorough
guy.

If the road was built to carry the traffic in the first place, it would
carry it.
The road I referred to in last message is still in fine shape, without
holes, patches or any resurfacing since early 70's.  It's carried
substantially more weight that any highway is regularly subjected to, gvw's
in the neighborhood of 150000# were common (they ran v12 detroits too)  US
restricts trucks to 5 axles and 80000# for the most part, speed is a huge
factor in thin topping roads.  I can't for the life of me remember the
researchers that did the study here, but they were examining the effects of
7and 8 axle trucks of 62,500kg or 137,750# with high sped photography, and
measuring the deflection.  the bulges between axles were impressive, and
likened to travelling ice roads over water, where you ride the crest of the
wave.  If you go too fast, you go over the top of the wave, and break
through.  IIRC, the magic speed was around 85kph as found in the study
Beyond that the wear to road surfaces was extraordinarily high.

That still doesn't change the fact that if directed taxes were spent on the
purpose they were collected for, it would be for the better.
-james

-----Original Message-----
From: vwdiesel-bounces at vwfans.com [mailto:vwdiesel-bounces at vwfans.com]On
Behalf Of Val Christian
Sent: Wednesday, March 01, 2006 9:14 AM
To: vwdiesel at vwfans.com
Subject: [Vwdiesel] Per mile costs


Forwarded message:
>  I agree that big trucks damage roads more, but the piper is being paid,
> believe me.  thing is, the piper toodles off to the bar at the end of the
...
>
> While the big trucks do use more fuel, the amount of road damage they
cause
> is MUCH more than the amount of fuel that they use.  They use about 4 to
10
> times the fuel of a diesel pickup truck per mile but cause more than 20
> times the road damage.
>

In 1978, while driving a Diesel Rabbit, I got curious about the wear and
tear on the road.  I did some rather extensive research on the matter,
and wrote a paper, which unfortunately is not in electronic form.

Salient points:

-A US GAO study found that one truck, loaded at 50,000#, traveling at 55
mph,
caused 9,600 times the wear of one passenger car doing the same speed.

-The wear factor on roads can simplistically be thought of as:

	WearFactor = (weight ** 2)  *  (speed ** 2) * (roadconstructioncoef)

Note that this GAO study was done when common speeds were much lower,
and the max weight of a truck was much less.  A quality road buys you a lot,
but it's inescapable that weight is the biggest factor.  Looking at a
typical interstate, the cost to run ALL the cars and light vehicles
over the cost of one day are less than ONE truck, from a road wear
perspective.

Of course there are other costs and needs associated with road maintenance.
Including median and shoulder maintenance, rest areas, police coverage,
enforcement revenue, etc.

Val
_______________________________________________
Vwdiesel mailing list
Vwdiesel at vwfans.com
http://www.audifans.com/mailman/listinfo/vwdiesel
--
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.1.375 / Virus Database: 268.1.1/270 - Release Date: 2/27/2006

--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.375 / Virus Database: 268.1.1/270 - Release Date: 2/27/2006