Concrete is an important material for making different buildings and structures. It is a composite made of Portland cementsandgravel or aggregate, and water in varying proportions depending on the task.

Concrete is used more than any other man-made material in the world.[2] As of 2006, about 7.5 billion cubic meters of concrete are made each year—more than one cubic meter for every person on Earth.[3]

The ingredients are mixed together into a paste, a bit like making dough for bread. The concrete is then poured into a frame. After a few hours it sets hard. Concrete solidifies due to a chemical reaction known as hydration. The water reacts with the cement, which bonds the other components together, eventually creating a strong stone-like material.

Concrete Floor Building Free Photo

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