Calculating load for barn floor

[FCStorm]

TL;DR Summary

Tractor weighs 6500 lbs. Floor is rated to 45 psf, with floor area of 390 feet. Safe to park tractor on floor?

I have a barn that with a central bay that was originally designed for supporting hatywagons, so it's undergirded by three huge tree trunks used as beams (running longitudinally, parallel to wheel tracks). It has previously been rated by an engineer as being capable of supporting 45 psf at its weakest point. The wagon bay is 390 sq2. Can the barn support a typical 4 wheel wagon loaded with conservatively 6500 pounds of hay? Assume the decking is up to the task: two layers of planking running at right angles and previously okayed by the engineer?

 

[berkeman]

Welcome to PF.

It has previously been rated by an engineer as being capable of supporting 45 psf at its weakest point.

What's psf? Pounds per square foot?

Can the barn support a typical 4 wheel wagon loaded with conservatively 6500 pounds of hay? Assume the decking is up to the task: two layers of planking running at right angles and previously okayed by the engineer?

Why aren't you asking the engineer this question?

 

[FCStorm]

Welcome to PF.


What's psf? Pounds per square foot?


Why aren't you asking the engineer this question?

He's no longer around.

 

[berkeman]

He's no longer around.

What did you do with him?!!

And why don't you go to the same agency to ask for a different engineer?

 

[Vanadium 50]

Why aren't you asking the engineer this question?

He was killed in a barn collapse.

Kidding aside, I don't see how we can answer this. The tractor sits on tires, so you have a few thousand pounds per square foot at the contact points. "Ah", you say "but the load is distributed through the floor and its bracing". Well, maybe so, but there is no way for us to calculate this.

 

[Baluncore]

I have a barn that with a central bay that was originally designed for supporting hatywagons, so it's undergirded by three huge tree trunks used as beams (running longitudinally, parallel to wheel tracks).

6500 lbs, most of that weight is on the rear axle. Say 3000 lbs per rear wheel. Tire pressure will be about 18 psi, so tire contact area will be 3000/18 = 167 sq in, = 13" x 13" square of floor.

The supporting structure should be investigated to identify if it will safely support those two tire contact patches of 3000 pounds each.

I doubt it will be safe. How do you know that the tractor wheels will always be above the beams?

You must consult an engineer about the load-spreading nature of the floor boards, joists and beams.

 

[berkeman]

You must consult an engineer about the load-spreading nature of the floor boards, joists and beams.

Agreed. This thread is closed for safety reasons.