Concrete is quite porous and acts like a sponge. When temperatures drop and concrete is wet, it can freeze, causing cracking and spalling or chipping. You can minimize this damage by periodically sealing the concrete with an acrylic or silicone-based concrete and masonry sealer.
A liquid concrete sealer prevents water absorption by filling the pores of the concrete. Generally clear, a concrete sealer lasts for six months to a year depending upon the quality of the material, surface preparation, and the climate.
Inexpensive "water seals" don't offer the level of protection that some of the more pricey products do. Moreover, poor-quality sealers need to be applied more frequently and can end up costing more money in the long run.
Concrete sealers can be applied with a brush, roller, or by using a pump garden sprayer. Before you begin, the concrete should be clean.
Rock salt used to melt snow is another primary source of deterioration of concrete. Sealer can also help protect the concrete from salt damage. After the snow melts, rinse the area with hot water to remove the majority of salt.