New Asphalt Driveway - How Soon to Drive Tractor over it?

[Diggin It]

My edges look like post 32. I laid gravel for about 4" and let the grass encroach to there.


Cost me $5K in '07 or so when I was still working. 180' or so length, 10' wide for the drive expands out to 25 or more for the apron. Don't even want to know what it would be now.

 

[skipperbrown]

Our HOA put down a 2" layer on top of a 20 yr old 2" layer on a 8 ft wide walking path around the hood. It only gets foot traffic. 6 months later, wherever the path went under a tree drip line, the asphalt is buckling. Now 18 months later, it is so bad it's a trip hazard and the HOA is looking at replacing hundreds of yards of path (at great expense). Pine trees, oak trees, Crepe Myrtle, Bradford Pear, it doesn't matter, the roots swell/grow and push up and break the asphalt. The asphalt was laid on a sandy base and not built up gravel. I hope your base is deep enough to prevent this from happening. If you see it start, I would seriously think about removing the tree. It's got to grow and the roots will lengthen and get bigger.

 

[HKUSPnut]

Cost me $5K in '07 or so............Don't even want to know what it would be now.

This was a $9k job which was fairly consistent with what others were quoting in my area. This contractor gave me the best upfront feel for competence and quality. The crew was really good and everyone seemed to know exactly what to do and when to do it. Not a lot of direction was needed by the owner/supervisor. They all seemed to work well together. The way a crew interacts and jives together speaks volumes to me about what kind of a company it is.

 

[HKUSPnut]

....Now 18 months later, it is so bad it's a trip hazard and the HOA is looking at replacing hundreds of yards of path (at great expense). Pine trees, oak trees, Crepe Myrtle, Bradford Pear, it doesn't matter, the roots swell/grow and push up and break the asphalt. The asphalt was laid on a sandy base and not built up gravel. I hope your base is deep enough to prevent this from happening. If you see it start, I would seriously think about removing the tree. It's got to grow and the roots will lengthen and get bigger.

Where the heck were you a week ago before I had my driveway paved!!!!! I hadn't considered root issues. :mur: My tree well is about 16" deep. The roots beyond the well have about 10" of sand, 3"+ of gravel, and 3" of blacktop over them. Hopefully enough to keep roots from becoming a problem in the next decade or longer.

 

[Diggin It]

This was a $9k job

Doesn't sound too bad really.

Hopefully

I usta' have hopes.

 

[ruffdog]

Where the heck were you a week ago before I had my driveway paved!!!!! I hadn't considered root issues. :mur: My tree well is about 16" deep. The roots beyond the well have about 10" of sand, 3"+ of gravel, and 3" of blacktop over them. Hopefully enough to keep roots from becoming a problem in the next decade or longer.

I would have been concerned of the tree being able to get water out at the drip circle on the one side. It is too close to the house for a problem tree so it would have been turned to firewood.:2cents:

 

[orezok]

Consider Newtons third law. For every action there is an equal and opposite reaction. Therefore if you have 35psi of air in your front tires, the maximum pressure per square inch applied to the asphalt is 35psi. Now that pressure is applied over many square inches. That is why the tire patch increases as you add weight to the loader. If you have a 3500# load on the front axle no square inch of the front tire will exceed 35psi.

 

[ruffdog]

I bet this thread will exceed 9 days..................:laughing:

 

[chim]

......................Therefore if you have 35psi of air in your front tires, the maximum pressure per square inch applied to the asphalt is 35psi...................................

Cool. I'll let half the air out of my tires and the tractor will weigh half as much

 

[HKUSPnut]

Consider Newtons third law. For every action there is an equal and opposite reaction. Therefore if you have 35psi of air in your front tires, the maximum pressure per square inch applied to the asphalt is 35psi. Now that pressure is applied over many square inches. That is why the tire patch increases as you add weight to the loader. If you have a 3500# load on the front axle no square inch of the front tire will exceed 35psi.

Interesting point. Not something I've ever thought about. Admittedly I am too far removed from school and out of practice for these types of discussions, however I think the way you have explained would be true if a tire had no tread (perfectly smooth surface).
Tread style must come into play. Well, I suppose tread style AND the intermediate layer of rubber between the air on the inside and the tread lugs on the outside. For illustration consider that you drove your tractor up onto 4 ea. 6" diameter flat rocks (one under each tire). The surface area at each tire is 28.27 inches squared. Multiply times 4 and you have ground contact of 113.1 square inches. If your tractor weighs 8,000 lbs and were loaded so that you had even distribution to all 4 wheels (we know this not to be the case during normal operation of a tractor) you would have an average contact pressure of 8,000 lbs / 113.1 = 70.73 psi. That far exceeds the air pressure within the tire. Remember the air inside a tire, inflated to a specific pressure is not just resisting the force of gravity on the contact patch, it's also reinforcing and preventing the sidewalls from buckling or collapsing. When PSI of ground contact exceeds internal tire pressure, something else in the system compensates. A tractor tire that rolls over a small pointy rock certainly exceeds the air pressure of the tire at the small contact point. Is it the elasticity of the tire, the sidewall, something else I'm not thinking of that compensates for this? I honestly don't know. I think we can all agree that given the same tractor, agricultural tires will leave imprints where turf tires will not. This is primarily a function of the tread design and the distribution of load between lugs and earth.