Sealing is the best way to prevent concrete from flaking due to moisture. For new concrete, apply a penetrating waterproofing sealant 28 days after the concrete is laid and every few years thereafter. The right concrete mix can also help prevent flaking. The second thing you can do is apply a water-repellent sealant.
Water-repellent sealants are a great solution for concrete peeling because they cause water and other liquids to peel off the surface. They reduce water absorption by up to 95%, preventing water from freezing inside the pores. Silicate sealants can be used in combination with water-repellent sealants if you feel that you need an increase in strength and a decrease in water absorption. If you apply both sealants, you would first apply a silicate densifier, followed by a silane siloxane water repellent sealant 5 to 7 days later.
To retain moisture and gain strength, all concrete must be properly cured. For flat work, it is particularly true that the upper surface is well cured. Membrane curing compounds applied by spraying or paint rollers are recommended. Cure concrete with a curing compound or airtight cover, then allow it to dry uncovered for at least 30 days before using antifreeze salts.
When concrete reaches its maximum strength, typically within 5-6 days, a simple reminder to seal exterior and garage floors a few months after installation can help maintain the surface for years. To prevent chipping concrete, mix one part Portland cement type 1 and one part fine sand by volume. Add water until the mixture has the consistency of a thick paint, then paint it on wet concrete.
Chipping
on a horizontal surface such as a driveway or sidewalk is not only an aesthetic problem, but also a safety hazard.To repair flaking on horizontal surfaces, coat and seal the surface with a resurfacing solution. The advantage of using this method is that it not only repairs peeling concrete, but also prevents flaking problems from reappearing. For outdoor slabs, sidewalks, and patios, use air-dragged concrete that meets ACI requirements. The descaling of concrete is the result of chemical and physical processes that occur within the concrete itself.
One technique that can prevent concrete from flaking is to apply a good water sealant to the finished surface to prevent water from entering the concrete. If entrained air bubbles are not present near the concrete surface to act as an internal pressure relief system, hydraulic pressure can easily overcome the tensile strength of the surrounding cement paste. Sealants are designed to reduce, but can never stop water absorption on the surface, meaning that exposed concrete remains at risk from the damaging effects of salt, snow and ice. The remedies for chipping vary depending on the severity of the problem, the type and location of the concrete structure and other factors.
Here, the top layer of concrete peels off, leaving the surface uneven and pitted while exposing the aggregate underneath. It is a relatively common problem with a number of causes ranging from the way concrete was mixed to environmental conditions. Concrete sealants are excellent solutions for protecting concrete, but in some cases, the use of a sealant alone is not enough. Without proper application of a sealant, concrete will absorb moisture and become a haven for mold, as well as being more susceptible to cracking, chipping and pitting.
If you have chipping on the wall of a basement or other vertical concrete surface, the solution can be a bit complicated. Overworking the surface can damage or destroy entrained air bubbles placed in airborne concrete. In many cases, concrete will need to be re-placed on the surface or re-poured to prevent the problem from continuing. The pressure built up by the expansion of water will cause glass to break - and that's exactly what it does to concrete.
