Driveway Preparation???

[Anonymous Poster]

I have been planning on extending my paved driveway alongside the garage. Now that the new tractor is here, I guess its time to get to work! The current area that will be used to extend the driveway is currently lawn. I have been using it to park on over the winter, and with the recent warm spells, it has gotten quite muddy. I don’t want to final pave it until I am completely done working in my back yard, but I don’t want to deal with the mud either. My plan was to excavated the area and then spread some crushed stone to take care of the mud problem for a few months with the hope that the pavers could then come in and just put the final grade in with asphalt.

My questions:
Does this make sense? If so, how deep should I dig, and how much and what type/size material should I use. How far below final grade (existing driveway) should the stone be as to minimize the amount of work the paving company has to do?

Ken

 

[WVBill]

Ken:

You'll get a lot of good advice from the folks here on TBN. Another resource is the Army Training and Doctrine Digital Library where you can download (for free) many of the Army publications. This link is to a page from one of the documents that talks about road building and may apply to your situation.

 

[Hoeman00]

I would dig out 12" of dirt and put 6" of 1&2 limestone (3-5") in for a base then after it gets packed in go over w/ 3" or so of 411 limestone (3/4" to fines).
A geo textile mat may help if ground isn't real stabile or on peat bog.
The topping is easy to move around and level then roll before paving.
This will leave 3" or so for asphalt.
The asphalt is only as good as the base.

 

[Anonymous Poster]

After removing 12 - 18 inches of soil my contractor ran over everything with a roller and a vibrating compactor. Then the black geo cloth, stone, etc as you described.

 

[gerard]

I agree with the previous posts for the most part - take out 12 inches to start, use the geo textile, then top with at least 6 inches of crushed base. Reason I would start with 6 inches is your plan to let the base compact "naturally". The biggest factor with road base is compaction compaction compaction, and this is best accomplished by layering and compacting between layers. Since you probably won't be doing that unless you rent some compacting equipment, you're going to wind up with decent compaction on the space you drive over regularly but not as good in the center where the tires never hit. By doing it in layers you can let things settle, (you'll get rutting where the tires go), and keep filling in until you're ready for the pavement contractor. Then he can come in, compact, put in more base, compact and top with the blacktop. A good contractor won't just come in and top something if he doesn't know what the base is because when it breaks up in a few years he doesn't want to be responsible. Bottom line - put down just enough base now to alleviate the mud and start allowing the sub base to compact. /forums/images/graemlins/smirk.gif

 

[Anonymous Poster]

Thanks for all the good advice. Point well taken about the paving contractor not just paveing over my prepartaion. I think I'll probably take the suggestion of just enough stone to take care of the mud and let the pavers do the rest. I'm gonna call for the utility mark outs tommorow, and hopefully get started next weekend.

Ken

 

[Anonymous Poster]

Do what we do for the general contractor I work for,
Call a paving contractor and ask them how much
base (and what kind) and what to top it off with
(for the type of paving you're going to use).
I had an asphalt contractor tell me one time
that an extra 2" of base could add 10 years to the
life of an asphalt driveway.
Use a reputable contractors advice and you should get the
best result.

 

[Racechaser69]

How about a situation where you are having to dig down about two foot to get rid of soft boggy dirt and reach hard clay? I was going to fill it (once dug out) with about 18" of clay then compact with a drive on compacter/roller.Then fill another 18" of clay and compact. Then place terra tex mesh over driveway and cover with gravel.

Many of you suggested the terra tex first then a layer of gravel, then the fill.Is this still your opinion if your dealing with clay bottom? Wouldn't the clay pack as hard without terra tex down first.

I'm not asphalting my driveway for several years if ever. I just want potholes and sunken ruts to be minimized. My driveway is about 15' wide by 300' long. So you can see a gravel base 6" deep, then fill, then more gravel would be expensive even hauling it myself.

Thanks
Scott

 

[Racechaser69]

no opinions?????????

 

[Casimir]

Racechaser69:

My opinion is probably worth about what you are paying for it,but here goes: /forums/images/graemlins/smile.gif The concern I would have about a clay base, even compacted, is that when it gets wet (like after heavy rains or snowmelt), the clay may get soft and the "bottom go out" on you. Not as bad as if it was on the surface, but you may still have problems. The gravel base, particularly if the first layer is larger (up to 2-3 inch), tends to spread the forces of compaction over a larger area than just directly under a tire. It has to do with all the angles of the rock pushing at different angles, if I remember my one civil engineering course from 35 years ago correctly. The geotextile may help to spread the forces some, but a deeper gravel base would help. IMHO /forums/images/graemlins/crazy.gif

 

[Racechaser69]

Well having taken 0 civil engineering courses myself I''ll say you're opinion makes sense. I guess I'll begin to consider the layering of gravel in with the clay.

Anyone else with suggestions will be greatly welcomed. The more details the better.

Thanks
Scott

 

[Anonymous Poster]

I'm just a simple dirt farmer with a very muddy 1/2 mile sand driveway in the frost-boils of Minnesota.

I think your bottom gravel layer will act as drainage. That is good, if the water drains away somewhere. That is bad, if the water drains to a low spot of the driveway & ponds there under your clay & top gravel. Will the water have someplace to escape the system & get away from your driveway? Then it sounds pretty good.

The textile under your gravel just holds the gravel seperate from the clay. Without it, they can mix a bit as the frost comes out & heavy loads run on the soft soils. Fabric makes the gravel act a bit more like a slab of concrete, with less expense.

Some would mound up the clay, put a thin layer of gravel, compact, lay the fabric, and apply a good layer of gravel. (Most wouldn't go to the expense of the fabric.) The theory is the water runs out on the gravel layer, and the clay stays firm. Would either save the cost of the bottom gravel layer, or add it to the top where more is always better it seems.

My understanding is compaction is the key, both clay & gravel layers. The bottom layer of gravel can be courser stuff, to spread the load more &/or drain better.

--->Paul

 

[Soundguy]

I don't think you'll want my opinion... but I think that if you are ever going to asphalt this.. you'l learn to hat that clay bed. Clay changes volume as its moisture content changes. Asphalt won't like contraction and expansion, and will crack.

Same reason why we excavate clay out from under road beds, and home foundations.

If this is a temporary drive.. gravel it and go.. spend your money later on the asphalt. If this is a ten year project, that changes a bit, as you'll need a serviceable drive...
I would not use a bottom gravel layer if it will be above grade. It will eventually extrude out. If below grade, and the sourounding material is as wet as you indicate.. it is going to be difficult either way.. but the garvel with a technical fabric over it,, then clay, then finish gravel sounds like a safer bet.

Soundguy