Things You'll Need
Concrete bonding liquid
Concrete mix powder
Concrete walls are widely used because they are easy to form and durable once they set. After the concrete has cured, however, it does not easily bend to outside forces. Movement in the ground where the concrete wall has been placed can cause the appearance of stress cracks on the surface of the concrete. Though not worrisome, these cracks can mar an otherwise appealing wall. With a simple patching method, you can repair these imperfections and revive the wall's appeal.
Wedge the chisel into the top of the crack in the concrete wall. Hammer it gently with the rubber mallet to widen the crack to approximately 1/2 inch. Repeat this process down to the bottom of the crack.
Brush out the concrete chippings with a wire brush.
Paint the concrete bonding liquid along the length of the crack. Be sure to cover the back and sides of the crack.
Mix together a concrete powder with water as described on the packaging instructions. The concrete should have the consistency of peanut butter.
Scoop the freshly mixed concrete into the crack to fill it from top to bottom.
Use the point of the trowel to pack the concrete inside the crack.
Sweep the flat side of the trowel over the wet concrete to level it with the existing concrete wall.
Allow the concrete repair to dry for 15 minutes, then brush it with a moistened broom to add texture.