Need Some Concrete Help

[J.A.F.E.]

My driveway has some damage I would like to fix. Someone was here before so I have that to add in. There are two spots in the driveway I don't want the repair to fail like this one did.

There is also a crack in the walkway. The area of the crack appears to have been replaced at some point and while the photo doesn't show it slab is low at the spot where it's cracked as both sides slope towards the crack - like the soil underneath has a void.

I have never done any work with the stuff so any help would be appreciated.

[Uncle Buck]

No expert here either. In recent years a number of two part epoxy fillers are now on the market to deal with bigger holes and missing chunks. I suspect there are likely special purpose chalks made specifically for filling smaller voids like cracks. I would guess you would apply a concrete sealer over whatever repair solutions you use to protect against the weather and further damage. I would probably do some Google searching if that was my situation.

[J.A.F.E.]

Thanks UB. I will do some research on these and see what I can dig up. I never thought about epoxies but it could be just the ticket.

[bonneyman]

Only tip I can offer on concrete repair is don't let it dry too fast. Weakens the structure, and it likes to crack. Pool installers told me they have the owner go and spray a nice water spray over the fresh pool install several times a day for like 2 days so the surface doesn't dry out faster than underneath. In the Tucson desert it's a must.

I did a concrete coating over so bare rocks along the property line next to my shop and it has several cracks now (years later) as I didn't know to keep it wet.

[oldnslo]

It appears the chipping is due to the concrete pinching. You may want to saw cut it at that point (before repair) so there is room for expansion afterwards.

[Heiny57]

It does look like it needs relief joints cut to stop the chipping. The trouble with that is they have to go somewhere. I don't know how far you would need to cut to make it work. There are several brands of concrete patching products that might work. Lowes Depot carries Seka products that may work, or Ardex is a more professional brand that we use sometimes. Remember a patch is a patch and always will be. Some work some dont. One trick to keep from making a mess is to clean the area well and let dry, then use duct or wide masking tape to tape off the area so you don’t make the patch bigger than needed.

[J.A.F.E.]

Thanks guys. Would the relief cuts be along the joints?

This is really helpful advice. I am completely new to this.

[oldnslo]

Yes, the saw cut is in the expansion joint, and goes completely through the slab.

[J.A.F.E.]

Thank you. I will do just that.

[highland512]

Do you deal with freeze & thaw? The places where you have cracks are cracked, not much you can do about it. If you want to fill the crack, get a diamond wheel on a 4" grinder and grove the crack about 1/8"-3/16" deep then fill the grove with a self-leveling concrete joint filler. https://www.lowes.com/pd/Sika-10-1-oz-Gray-Crack-Flex-Sealant/999977060

If the areas where the corners have crumbled are bugging you, there are a couple options you have.

1. Roughen the existing surface and use a masonry repair product https://www.lowes.com/pd/Sika-1-Gal-Acrylic-Concrete-Patch/1002780038
The product label states not to exceed 1/4" but in your case you will have to exceed it, this is not a permanent fix and will most likely fail after a few years. Try to keep the existing joints preserved while using the patch material.

2. Cut out the bad areas and pour new.

[J.A.F.E.]

Thank you. I got the Sika. I suppose for now the patch will be the solution. On a longer term basis I guess I'll just have to cut it out and pour new. I'm not opposed to doing it but right now time wise the patch works better.

No, it does not really freeze here - I live in the Mojave desert.