Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here


Ground pressure per wheel set?

Ground pressure per wheel set?

Ground pressure per wheel set?

I am looking for either guidance or a formula for calculating ground pressure per wheel set for a truck and trailer that has a capacity up to 80,000 lbs. The tandem axle capacity for both front and rear is 34,000 lbs each and the capacity for the front steering axle is 12,000 lbs. Thank you.

RE: Ground pressure per wheel set?

I don't understand the question. If the truck is loaded to capacity and the weight distribution is correct then the ground pressure is 6,000 lbs per front wheel (12,000 / 2) and 4,250 lbs per wheel in each tandem set (34,000 / 8).

The suspension design in the tandem axles is normally designed to evenly distribute the load between the two axles, and the side-to-side distribution is the operator's responsibility to load the truck correctly, and a good many transport trailers have the ability for the trailer's tandem axle to be shifted fore/aft to get the weight distribution right, in addition to the operator's responsibility to load the truck correctly.

RE: Ground pressure per wheel set?

Thank you. I am reading between the lines of a scope of work that I am quoting for a potential customer. None of us in 30 years rigging, trucking and mechanical engineering have ever heard this particular term (ground pressure per wheel set). They specifically asked for the capacity of each truck and ground pressure per wheel set. It seemed too obvious, that they would be asking for equal weight distribution on each wheel since the capacity is already known. I was wondering if they were looking for pounds per square inch of each of the set of tires footprint. I was hoping someone had actually heard this particular term-(ground pressure per wheel set.) Or that there was a formula for converting truck tire footprint to psi when under a full load. Thanks again.

RE: Ground pressure per wheel set?

The 5th wheel location on the tractor can also be tweaked a bit fore/aft, again as a means of managing load distribution.

Don't overlook lateral load transfer due to cornering and longitudinal load distribution due to braking or acceleration.


RE: Ground pressure per wheel set?

You need to ask the customer for education about what they mean.

It smells like they don't know the difference between pressure and force.

Mike Halloran
Pembroke Pines, FL, USA

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close