Concrete is damaged by salt most often at joints or cracks
Magnesium cements offer a permanent repair to concrete that uses less energy in production and use than traditional Portland cement.
We are seeing increased failures in concrete sidewalks and driveways. Most early degradation of concrete is only caused by two basic forces; improper installation of the concrete and uses of deicing agents in cold climates.
Poor installation techniques can be remedied by following basic standards for concrete installation. However, there does not appear to be an easy remedy to reducing the use of salts for ice removal. Property managers are using more salt in a belief that they will be sued by injured parties if they don’t keep parking lots and sidewalks clear of ice. Salt usage causes damage to concrete through the freeze
and thaw action that it creates.
Our experience is that Portland cement patches only last about a year
Once this process begins, concrete degrades rapidly. Usually, damaged concrete sections are cut out and removed or entire surfaces are replaced. This is a costly endeavor and there is no guarantee that the new concrete will last any longer than what it replaced. Most Portland cement patching mixes for concrete, simply do not last more than a year or two in this climate.
Magnesium oxide and magnesium phosphate cements were the primary mortars for over two thousand years. If you see a standing ancient building or wall, it was probably constructed using magnesium cement mortar. Magnesium patching mixes are available today at some concrete outlets so you can use this ancient technology to save your concrete.
BASF makes a type of magnesium patching material
It can be difficult to determine which mixes are magnesium and which are not, so reading the ingredient list is important. Plan to pay about $50 for a 50 pound bag of mix. That is a steep price, but since you can add 60% additional aggregate, this makes the purchase more reasonable.
We have tested magnesium cement and found it to perform better than any other patching material. Something that lasts is indeed green and helps keep the “green” in your wallet.
Magnesium cement hardens in only about 10 minutes. So, it is best to have a helper other than your spouse when you start yelling!
Coating the existing edges of the repair with magnesium cement helps seal the patch
60% aggregate can be added to the mix without significant lose of strength