Driveway Preparation???

[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