How to fill cracks in concrete
If you’ve found some cracks in your concrete you can fill cracks that are larger than 1/4 inch easily with concrete patching compound. First you need to clean out any dirt out of the crack (Use a vacuum if needed) The next step is to brush on some acrylic bonding liquid which will give extra strength. You then press the compound into the crack using a trowel, clear away any excess that maybe left behind before the mortar dries.
Small Cracks
If the crack is smaller then 1/4-inch use caulk to seal. You can use Silicone- or acrylic-based products, which can easily tolerate small movement without failing.
Large Cracks
If you bore some hole into the edges of the damaged concrete, somewhere in the region of 1/2-inch diameter x 2-inch deep holes. you then need to use anchor cement to secure 1/4×4-inch bolts in to these holes. The exposed part of these bolts will help secure the patch in place.
The next step is to mist this area with water and put a plastic cover over it for a least a week, this will help extend the curing time and strengthens the patch.
