Crack-Pac® Injection Epoxy | Simpson Strong-Tie- Concrete Wall Crack Repair Materials ,The Crack-Pac injection epoxy is designed to repair cracks in concrete ranging from 1/64" to 1/4" wide in concrete walls, floors, slabs, columns and beams.Concrete Surfaces Crack Repair - Sherwin-Williams - YouTube · One of the most common problems when it comes to concrete is cracking. Walk through the right products and basic tools needed to repair most cracks and give aging concrete a …