Page 40 - Curriculum Visions Dynamic Book

trap the aggregate. In this way the correct structure develops inside the concrete. During the curing process concrete is often covered with plastic to protect it from frost and heat. Most of the hydration and strength gain take place within the first month
of concrete’s life cycle, but hydration continues at a slower rate for many years. Concrete continues to get stronger as it gets older.
A concrete mixture that does not have enough paste to fill all the gaps between the stones is difficult to work with and produces rough, honeycombed surfaces and porous concrete. A mixture with an excess of cement paste is easy to work with and
(Above and below) Reinforced concrete is very common in large- scale construction. The bridge below and the skyscraper pillars above are being built using concrete reinforced with steel bars inside the concrete. The steel bars help provide flexibility to an otherwise brittle material.
(Left) Concrete forms the core of this skyscraper. If you look at a city, what you mostly see is concrete and road surface materials.
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