How much will this cost us?

Francesca Knowles wrote:

bid_time wrote:
Increasing the load by 12.5% increases the road wear by 42% - BULL!!

THERE IS NO STATISTIC TO BACK UP THAT HYPOTHESIS.

Well, yes, there is/are; though it's not a "hypothesis", it's a plain fact. If anything, it actually understates the impact. I s'pose there are national variables due to weather etc.

For those who understand enough engineering/"non linear" math to absorb the data, here's a link to a fully annotated/backed up document. It's from Minnesota, and represents one of the studies that finds the damage increase to be even greater than that estimated above. Do please note the language per "geometric rate". Damage isn't straight-line related to beginning number.

A conventional five-axle tractor-semitrailer operating at 80,000 pounds gross vehicle weight (GVW) is equivalent to about 2.4 ESALs.
If the weight of this vehicle were increased to 90,000 pounds (a 12.5 percent increase), its ESAL value goes up to 4.1 (a 70.8 percent increase), because pavement damage increases at a geometric rate with weight increases.

Link to source

Maybe you can direct me to the table that says 12.5% increase in Load causes 47% more damage to the road. Because an increase in ESAL does not cause a straight line increase in damage. There are hundreds of varialbes. The easiest one for you to comprehend is pavement thickness. A 1000 psi load on a 48-inch thick, 6000 psi concrete pavement won't cause any more damage than a 890 psi load (12.5% increase). Before you start talking about ESAL you need to know something about CBR.

That would be like saying if you drive your smart car over your driveway its safe. If you drive your pickup over your driveway (whichs weighs double) it'll crack. It doesn't work that way.

Sorry, but your ESAL is all about load. There is no correlation that says a increase in load increases damage.

Now I'm going to repeat it for you:
Increasing the load by 12.5% increases the road wear by 42% - BULL!!