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RE: Amazing facts





Well, if you assume a typical 18-wheeler, 60-70,000 lbs, and truck tires
having an estimated 4x the contact area of a car tire, then there is less
than a factor of 2 in pressure between car and truck. Of course the
loads aren't really distributed evenly over all the tires, but a factor of
2-3 in pressure between truck and car then moves us back to overall force
as the culprit (if we are to blame the trucks for the damage).

Rick


That's not all together suprising: why design stronger tires and
bigger pumps to fill them to higher pressures so that trucks can
exert a high pressure on the road when you can just spread the load.

I wonder if it is pressure that does the damage: after all your truck
is putting its pressure on to the road at 18 points of contact, each
covering four times the area of a car tire ... On the other hand I
guess some critical stress has to be exceded in order to do any permament
damage.

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