In the most general sense of the word, a cement (click here) is a binder, a substance that sets and hardens independently, and can bind other materials together.
Four essential elements are needed to make cement. They are Calcium, Silicon, Aluminum and Iron.
Calcium (which is the main ingredient) can be obtained from limestone, whereas silicon can be obtained from sand and/or clay. Aluminum and iron can be extracted from bauxite and iron ore, and only small amounts are needed.
The word "cement" traces to the Romans, who used the term opus caementicium to describe masonry resembling modern concrete that was made from crushed rock with burnt lime as a binder. The volcanic ash and pulverized brick additives that were added to the burnt lime to obtain a hydraulic binder were later referred to as cementum, cimentum, cäment, and cement.
Concrete should not be confused with cement, because the term cement refers to the material used to bind the aggregate materials of concrete. Concrete is a combination of a cement and aggregate.
The aggregates of concrete are generally a coarse gravel or crushed rocks such as limestone, or granite, along with a fine aggregate such as sand. Sand is always in the mix.
Concrete (click here) is a composite construction material composed primarily of aggregate, cement, and water. There are many formulations, which provide varied properties. The aggregate is generally a coarse gravel or crushed rocks such as limestone, or granite, along with a fine aggregate such as sand.
There is so much concrete in the world it is now being recycled.
Construction and demolition waste (click here) generation has exceedingly increased around the world. In Australia, about 40% of construction and demolition waste is generated annually. Out of various types of construction and demolition waste, concrete constitues about 80% of the total waste. Therefore, it is necessary to recycle concrete waste to recycled aggregate and recycled aggregate concrete.
Nowadays, almost all demolished concrete has been mostly dumped to landfills. As concrete is an essential, mass-produced material in the construction industry, efforts have been made to recycle and to conserve it....
