Could you offer a solution or any helpful suggestions to a problem concerning patching spalled concrete? The condition exists on the floor of a meat locker in a restaurant: The floor is subject to constant freezing temperatures; raising the temperature would be damaging to the business. Health Department regulations require the floor to be a smooth and cleanable surface. If repairing with cement is impossible could you suggest any other type of application?
The temperature in the meat locker is probably between 32 and 38 degrees Fahrenheit. This is too low to make successful repairs with the otherwise very useful epoxy compounds. With some improvisations, it might be possible to make repairs with a rich floor topping concrete mix, but that requires special precautions. Outlined is a method which may work, however. The patch should not be less than one inch thick. The base concrete must be roughened and cleaned. As the base is cold it must be warmed up, which can be done by using infrared heat lamps or by covering with an electric blanket. The concrete mix should be 1 cement-1 sand and 1 1/2 parts 3/8 -inch grits or stone. The cement should be Type III or Type IIIA, the mixing water heated and an accelerator such as Sika "Quick Set" added. The finished concrete should be covered with wet burlap and an insulating cover or the electric blanket for 48 hours. Whether this can be done depends on the condition in the cold meat room. An alternate would be to cover the damaged area by laying quarry tile on a prepared base with quick setting mortar.