My driveway is completely paved with concrete except for the last 10 feet or so where it connects to the street, which is just compacted gravel. The gravel is a nuisance and I want to remove it and pour concrete in there (which is allowed, as most of my neighbors have it). I need it removed to 4 - 6" in order to pour the slab, but I can’t get more than about 2 inches deep without hitting ridiculously compacted dirt/gravel. The shovel just bounces off it. A rake, hoe, or fork eventually bend, and I don’t get much progress. I can break it up with a pickaxe, but that is some work. What I need is
a) an easier way to break up the soil without destroying my nearly 50-year old body or
b) someone who knows this stuff to tell me it’s OK to just pour 2 inches of concrete over top of this heavily packed stuff and not worry about driving on it, because it will be adequately supported.
I considered a rotary hammer/chisel…this will make the work quicker, but it still beats the ever loving out of you. I know this because I used something like this to remove the tile in my kitchen before the remodel. But I’ll re-consider it if it’s truly the best tool.
So, outside of renting a backhoe, how should I approach this?
The standard way to do this would likely be a pick-axe. (While singing “I’ve been working on the railroad, all the live-long day ♫”) That breaks it into manageable chunks for the shovel. I guess it depends on your back, energy level and determination.
I have attempted to use the pickaxe. I bought one specifically for this. This is some hard-ass stuff. After about 15 minuts I had carved a 4-inch wide path about 5 feet long, and maybe 4 inches deep. It would take me days and a costco sized bottle of motrin to do it this way.
Dynamite is right out, as I am in the city.
I have tried getting it wet. Then all I have is wet, compacted stuff that makes an unholy mess when I hit it with the pickaxe. I also tried a pressure washer, thinking the high pressure could blast into it. Maybe, but I’d probably use 1000 gallons of water trying, and I don’t want to be that wasteful.
When I was making an opening in my basement slab to relocate a toilet, I rented a small electric jackhammer for the day from Home Depot. That might be your best alternative if it’s pick-axe reistant. if it goes through concrete, it should go into packed gravel. Just do the same as with concrete, and break it up in chunks progressively along an edge.
Oh, I have one of those hand soil tillers, it is useless on this stuff. Imagine trying to use it on cement. The tines don’t dig in, so they just scrape along the surface.
Look up hydro-excavation. There are simple hand made tools that work from with a garden hose and ordinary water pressure. Pressure washers are also used. I think it might work to loosen up the compacted gravel but you’ll still have to scoop it up with a shovel.
Small jackhammer is great, I’ve rented one from HD to (1) remove a small concrete slab and (2) break through caliche (rock hard calcium layer that can occur just bellow the surface here in the desert) for planting some trees.
I recently picked up a 1” rotary hammer from Harbor Freight for $99 that would also do the job with the right bit, albeit a bit slower than the jackhammer.
I also find a pointed digging bar to be useful breaking up caliche and other types of hard packed surfaces. Less strenuous than a pick in my experience, and more precise for the untrained.
I’d be hesitant to rent a hoe of any size unless you really know what you’re doing. You want a fairly level and shallow excavation so you don’t get uneven settling after you pour the concrete. It’s pretty easy to dig too deep with a hoe when you’re learning.
Are you personally doing all the concrete work? Forms, sand, compacting, mixing the concrete, screeding/floating the concrete, etc…? Or having it done by a contractor?
I would hire it done and the contractor can dig (and probably has the equipment) to their specifications. Unless your time is free and your health is no concern, I would hire the job out.
Yes, I am becoming more and more inclined to do just that. I had thought to try to save money doing it myself, but having someone come and knock it out in one day would probably be better.
I little excavator can be rented for very cheap. A couple hundred dollars. The controls are very simple. If you have ever used a fork lift, bobcat, for any reason, you can operate one. There is no training required, “this makes it go up, this makes it go down, this makes it gor forward.” Hook up your truck to the trailer and bring it back in a couple days when you are done.
It’s not much more to hire someone with a backhoe or mini-excavator to do it in an hour or two. They’ll probably want at least half a days work paid for anyway so you can have them do any other digging on your property you might need. And you’ll have whatever is dug up to get rid of. If you can’t bury it or keep it somewhere on your property someone will have to load into a truck. If you’re not going to do it all yourself talk to a contractor and consider what a back operation will cost you some day.