need help with access road across steep slope

[Sodo]

I'm cutting in a roadway to access a little level spot on some steep land.
The access turns off my driveway above.
I want to park a vehicle on the level spot (under a small roof).

I'm first cutting in a preliminary road to the level spot, and will level it out first.
I plan to dump concrete rubble down from the driveway above. The rubble is free material, which I like.

Any comments? If the rubble ends up at a 1:2 slope is it stable to drive on without crushed rock drizzled into the voids?
And will geogrid hold the pile? I have lots of geogrid.
Do I have to use a tight weave geofabric ontop of the rubble between the topping soil and the gravel?

Lots of questions. If anyone knows of a good website, or youtube plx offer some links, or search terms.

The road is not as steep as it looks in this pic. But the sideslope is steep. What I'm trying to depict with the yellow triangle is the slope of the rubble, from the upper roadway edge to the lower shelf edge. (oops its 1:2 not 2:1)
Rubble will pile up on the preliminary road. I planned to use geogrid in layers on the prelim. road, arranging layers as it piles up.
The prelim. road is like a "support shelf' for the pile of rubble that the main access road will sit on.
Is this a good plan?

Looking from the pad back. The roadway grade down will start at the _base_ of the upper pile.
You can see the angle of repose down the bank. Thats the first 9 yds of free rubble. Free delivery too! And unlimited supply (they say).

Was thinking of building up the slope like this, except not nearly as steep, more like 1:2. Using geogrid as the pic on the right. I hope it will work as I already bought the geogrid.

 

[bcp]

Like your truck. I've had two, and one wagon.

Can you turn around on the bottom flat, or will you be backing one way? If backing, make the road wider if at all possible. It's hard to track within a few inches when backing. That 6ft width will have one side's tires right on the edge. How about when it is packed snow and slippery?

My original driveway was 8ft wide, and I had to back out about 200ft. I often got far enough out of line I had to pull forward and retry.

Bruce

 

[Sodo]

Will be backing down the slope. Agreed it needs to be wider for backing. Good point. Was going to try for 10 feet with 8 feet of gravel. Look at the driveway grade it's barely steeper than that.

It's a busy spring, got all kinda projects going.

 

[dragoneggs]

Sodo, I am looking forward to following this thread. I am on a steep unimproved hill and am looking to add access and parking/storing a trailer, etc. other than my main access to the high end of my property. Sorry, I don't hav much to contribute... yet.

 

[Streetcar]

Sodo
You are building an engineered fill
What type ,strength is geogrid?
Engineered fill is usually smaller aggregate to uniformly load the geo grid
What vehicles will be using this road
Will the concrete vary much in size

Good luck

 

[Streetcar]

Is geogrid rated for uv exposure

 

[DJ54]

I'll venture to say, that within a few years, what was cast out from the cut, and laid on that slope will slip, more than likely during the rainy season. If the bench cut would have been as wide, as what you wanted to park on, would have been all cut, it more than likely would set there, but still the overburden would probably sluff over the hill.

Even a series of stair step benches would have been better, but easier cut in with a dozer.

That hill is there for a reason, there is rock underneath. During the rainy season, water will soak down through, then perk out, at the level of the harder rock, then seek the easiest path of resistance to get away, out through the hillside. Time will tell.

 

[MossRoad]

Is geogrid rated for uv exposure

That would be my concern too, if its exposed like in the drawing. :scratchchin:

 

[Sodo]

You are building an engineered fill
yes (with luck, and help) Thanks very much for the assistance! I won't be able to do everything to municipal standards, but hopefully can do most.

What type ,strength is geogrid?
I don't know. (from craigslist). It's really tough stuff. That pic is from google, but mine is similar. Should I post a pic of what I have? I'll cover it with detritus then ivy will climb it, sheltered from UV.

Engineered fill is usually smaller aggregate to uniformly load the geo grid
yeah I'd rather have 1 1/2". I can imagine if one strand breaks then the next two are stressed higher. (if continued pressure or movement). But it will NEVER see a heavy truck, so I can't imagine what would break even one strand. And the rubble is free, delivered free, and 5 yds at a time, which fits my construction schedule.

What vehicles will be using this road
Its a dead-end spur. Occasional 4,000 lb going to/from a shelter at the level pad. Backing down, driving up.
The area where the vehicle will park on has been level for 40 years. Just hope the access 'behaves'.

Will the concrete vary much in size
Prob consistent to the pic. about 1 foot max dimension, and down to fist size.

Good luck
Thanks, I may need that too. If it settles a little I can re-level at the top.

Even a series of stair step benches would have been better, but easier cut in with a dozer.
No bedrock here at all. It's glacial till. All the trees are perfectly straight, there is no slope movement apparent in 70, 100 year old trees.
Don't have a dozer - I wish. I feel lucky to have the mini-ex. If tools are recommended that I don't have I can't do it. If wishes were horses...... What I'm wishing for most is a place to park a vehicle, that doesn't cost more than the vehicle.
All I have is the one (additional) stair step to hold the foot of the geogrid layup. I'd like ecoblocks there, but don't have eqpt to move 6,000 lbs. Gabions would be good too. But the step is already cut in so I'm goin with that one stair step to hold the'engineered fill'.

 

[RNeumann]

Most little private driveways aren’t engineered. It’s quite typical to cut/fill while making a driveway and simply use the machine to compact in 6-12” lifts. Rip Rap helps with water erosion but isn’t really designed for retaining soil much above 4”.

My biggest concern with a road is the drainage. If that isn’t right (crown culverts etc) you can kiss a lot of your work goodbye when it rains. With regards to compaction- yes things will settle and move. Unless you plan to bring in some heavy equipment, possibly import material depending on soil type and have testing done odds are it will move. Movement is ok and normal as the road get compacted over time and with use. Simply add material as it settles.
Everyone has a different expectation of what geo fabric is. Wit a 2:1 slope I don’t think I’d put it on the slope unless their was a water issue I was trying to solve- see rip rap above. The place to use the fabric is on the road- lay the fabric and then use 4-6” of road base on top to finish out the road.

The photos look like you are doing a good job and your level of concern is more than most. I’m sure it will be fine.