Highway Vehicle Weight ```Name: patrick t seeman Status: N/A Age: N/A Location: N/A Country: N/A Date: Around 1993 ``` Question: Is there a formula for how the weight of motor vehicles effect highways? Replies: It is probably not just the weight of the vehicle that is important but the weight, number of tires supporting that weight and their total surface area exposed to the pavement. Therefore, I think that the pressure exerted by the tires on the road should be compared with the yield strength of the asphalt. You could probably find info on the strength of the road in a Civil Engineering Handbook. Check the reference section of your local library. david r munoz Damage done by a given vehicle increases roughly with the fourth power of its weight. Put another way, if you double the weight of a vehicle, then the damage it does gets doubled four times. This means that double the weight causes 16 times the damage. Spreading the weight over many wheels and many axles greatly reduces the damage caused per pound of vehicle weight. Also, axles spaced just a few feet apart do less damage than axles located individually when used on asphalt pavement. On concrete pavement, the damage is independent of the axle spacing. Cars do little or no pavement damage in comparison to large trucks. It takes approximately 12,000 cars to do the same damage as a single 80,000 pound 18-wheel truck. Engineers who design pavement typically ignore the number of cars and only concern themselves about the number of trucks. Andrew Johnson Click here to return to the Engineering Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012