Reasons concrete cracks

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Concrete is a relatively brittle substance by nature. It does not bend or flex under pressure. So when it shrinks, like it naturally does as it ages, the surface begins to crack. As times goes on, and the house situated above the concrete settles more with the weight of furniture, books, people, and what not. This causes stress in places there was no stress before. This kind of shifting weight can cause what are called stress cracks. Another, less common kind of crack is a structural crack. When the soil the foundation was built on is unstable and shifts unexpectedly, the foundation can get deep webs of cracks throughout, needed professional attention.

When wet concrete dries, the water is pulled out through the force of osmosis. In this case, osmosis is the reverse suction caused by the surface tension of the water. Because of this, the surface dries faster, and therefore shrinks faster. Were the substance not so brittle, it would curl, but rather it creates plastic shrinkage cracks. When the surface of the concrete heats and cools faster the lower layers, it can cause thermal cracks.

Another common reason for concrete cracking is when moisture seeps deep into steel reinforced concrete and affects the steel. The steel may rust, or expand, further cracking the concrete. Concrete found outside is particularly in danger, as the freezing and thawing expands and shrinks, (as does any water in the pores of the concrete.) Outdoor concrete can also be subject to the affects of road salts, or sea salts, both of which are very corrosive.

Eventual cracking is all but unavoidable, but professionals have founds ways to reduce the amounting and severity of the cracking and ways to save you money on repairs. Admixtures to slow drying, or to slow hydration, control joints, all will help avoid the serious side affects of this type of cracking.

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The reason concrete cracks