Rock type for gravel road? and culverts?

[JimS]

I have read quite a bit about this and there seems to be lot's of different opinions... Looking for advice.

I have a gravel road to a back field that gets little use but I would like an all season road to it. The road has good drainage (actually will have shortly). It has 2" base rock and smaller rock on top of that. The road has held up well for about 6 years but the trouble is keeping down the grass and weeds. I plan to resurface the road after some ditch work and am trying to figure out the best rock to use. I was leaning toward 3/4" or 1" clean rock to keep down the vegetation. But I also read how crushed limestone such as CA6/Grade 8 (at least that seems to be what it's called around here) packs well. Trouble is the fines promote seed sprouting. For drives that get a fair amount of use it that seems to keep the weeds down although there is still some growth along the edges and center. It seems like the best plan may be crushed limestone well packed, then a thin layer of clean gravel on top?
Have used roundup and similar but it doesn't last long.

And a question about culverts... Seems that poly culverts are popular. I haven't priced alternatives but I would guess that's because of low cost and light weight for easy handling. But the culvert that was installed (smooth bore) has been partially crushed - it was that way since installation. Others installed it and I think part of the problem was they ran heavy equipment over it without adequate cover and packing. I didn't notice it until after the job was done and paid for. I think the rule of thumb is 1 foot of cover minimum for good load bearing? Is this adequate with proper placement of material around culvert? Would I be better off in the long term with steel or concrete? Looking at one 12" and one 15" in different places. I did some measuring at it looks like I have just enough height for the 12" pipe with 12" of cover. The 15" pipe is no problem as I have lots of drop on the discharge side.

 

[JimRB]

I have never seen a gravel driveway that did not require moving. You can get soil sterlizers/plant killers. Weed Killer Herbicides Residual is one example.

We use, or I should say where I live the road in front of my house and my driveway before I put concrete on it was crusher run. I think it could be called 57 or maybe -2. All the sharp edges let the surface lock in. If you don't want weeds just get concrete at $100 a yard which adds up fast.

My metal culvert has a few inches of dirt and gravel over it but it never had any big loads on it. A few tandem axle dump trucks full of dirt and a few 10 yard concrete trucks. No collapsing that I can see. My truck is only 6,200 pounds empty although I did get a ton of fines in it to fill a horse stall.

 

[s219]

The rules around here say that recommended cover for poly is 1/8 diameter or 12", whichever is greater. But you can go down to 6" if asphalt is applied on top.

Around here, the minimum pipe size allowed is 15" ID / 18" OD. That will handle a 10 year storm event for roadside ditches. I think that size pipe can handle up to an 8 acre watershed in other applications.

Based on the rules in my state for culvert pipes and cover depth, poly and steel would seem to be a better option than concrete. You can get away with less cover height with poly and steel. That seems opposite of what I expected, but I am betting the steel and poly pipes handle live loads better.

 

[rsewill]

Build a nice road and spray the weeds. Inch and a quarter minus limestone 2" deep and then Roundup as needed.

 

[mjncad]

I have a recycled concrete driveway consisting of 3/4" gravel and road base, and I still have to spray it.

You don't say what part of the country you're in; but I'd inquire as to what local practice is.

 

[Gary Fowler]

You betcha, little used roads, even concrete with small cracks will have grass growing on them. For example look at an old abandoned air base or any abandoned road, they all have grass or even trees growing on them. That is natures way of reclaiming what man has upset. You can either blade it off to keep the grass at bay or as suggested just spray it with a herbicide yearly. Used motor oil on roadways used to keep grass at bay but that is no longer considered an option as our environmentalist published findings says it contaminates our waters.

 

[mx842]

Regardless of what type pipe you install you can bend,bust, crush it no matter what you put on top of it if you don't install the pipe correctly to begin with. Another thing, you don't decide on the size pipe to put in by how much dirt you can put on top of it the size pipe is dependent on what the water flow is likely to be for the given area. Your pipe needs a good base to rest on and any loose, wet soggy material needs to be removed and back filled with a good rock base and the ditch should be on a minimum of 16" wider than the pipe so you can get at least 8" of compacted stone under and on both sides of the pipe. If installed properly there is no weight on the pipe itself it's all on the compacted material the pipe is surrounded by so the material on top really offers no real weight bearing support. If installed correctly the top of the pipe could be showing and still not be crushed by heavy machine traffic. The main thing is to have a nice even level grade over the pipe that matches the grade of the road, not a speed bump over the pipe that will over time cause problems.

As far as trying to keep grass out of a gravel drive you are fighting a losing battle because no matter what you put down nature will find a way to sustain life where ever seed may fly, I've seen trees growing out of solid concrete bridge abutments. Packed stone seems to be better over loose stone and they stay in place better but you still will need to blade or drag the road down once in a while to keep it in shape.