A question for the concrete gurus

[tn_popo]

When anyone enters my narrow driveway they usually cut the corner short and drive on the grass causing a muddy rut when it rains. I plan on digging out the corner and forming it to extend the corner of the driveway. Can anyone help me with the best products to use for a DIY project? I have some rebar to use to strengthen it.

 

[1jjpop]

Drill adjacent concrete to tie the addition you are placing , so it won't go down.

 

[ssdave]

I would put a thin separation layer between the existing concrete and the new, to allow them to not stick together. A layer of tar paper will do nicely, usually. Then, tool a slight chamfer on the edge with an edger. Caulk the joint with urethane caulk when the job is done. Do Not Pin it to the existing concrete, most slabs are way too thin to pin to, and you will simply crack/spall the existing slab because of the pinning. To insure it doesn't settle, you need to make sure you get a good base under the new concrete. Dig out the subgrade under the new triangle, and put in a good solid 6 to 12 inches of gravel under the new concrete (depending on the stability of the subsoil as you excavate for the new gravel). For a piece this small, you can compact it by hand; use a flared head digging bar if you have one, or just use a 2x4 on end. Put in a couple of inches of gravel, wet it, and then pound it severely with the bar or 2x4. Repeat in 2 inch incements until you have it to grade.

 

[dakota98]

Unless the slab is more than 6" thick and in really good condition, I'd be careful.

Might consider using interlock stone instead of concrete. Make it look like a border for the driveway. Doesn't risk cracking the existing slab when you drill into it.

 

[fastevo9]

Yep the rock solves problems. I helped a friend put one in front of his house and to date 2 people have driven into it and mess up there cars.

 

[tn_popo]

How would one prepare the site for Interlock Stone? And are the "concrete pavers" at Lowes the same thing?

 

[ssdave]

You prepare for pavers similarly to concrete. Lay down 6 to 12" of compacted base, to 1" below the finish paver level. Compact as you would for concrete. Trowel the sand flat, and lay the pavers on it, tapping them tight against the existing drive or last row as you go. When you get to the edge, dig a small trench under the outside 1" or so, about 4" deep, and 4" wide. Pour mixed sackcrete into that trench, to about 1" up the edge of the last paver, to lock in the edge. Alternatively, buy the commercial edging strip and install per instructions. Pavers are an easy and good way to go, if they settle, you can pull them out and relevel with sand and relay them.

I am doing my entire driveway (1750 sf) with pavers at my new house I'm building. I really like paver, have done some large jobs (city streets, several blocks long) that are still in service and as good as the day they were placed 30 years ago.

 

[tn_popo]

So 6"-12" of sand as a base?

 

[ssdave]

So 6"-12" of sand as a base?

1" of sand as a leveling course, over 6" to 12" of crushed, 1" minus or 3/4" minus base course aggregate. This is the material that is used under asphalt in streets, or concrete slabs that are prepped right. Any good sand and gravel place that supplies the trades can supply it.

The function of the sand is to make it easier to level the top perfectly, so the pavers sit flat and don't tip or settle.

When you get the pavers all laid, you cover them with a thin layer of sand and then it is best to vibrate them with a plate compactor. On a small patch, you can tap the middle of each paver with a rubber mallet, moving around to hit all of them evenly. The vibration helps to settle sand in the cracks in the pavers, and settle them firmly in the sand base. You sweep the sand back and forth with a broom to aid in filling the cracks, until they will take no more. That greatly increases the long term stability of the job. You can buy a special sand called polymeric sand at home improvement stores, that binds together and helps keep weeds from growing. It's a good investment.

 

[tn_popo]

Thanks ssdave