Cement
- A cement is a binder, a substance used in construction that sets and hardens and can bind other materials together.
- The most important types of cement are used as a component in the production of mortar in masonry, and of concrete, which is a combination of cement and an aggregate to form a strong building material.
Cement History
- Joseph Aspedin of Yorkshire (U.K.) was the first to introduce Portland cement in 1824 formed by heating a mixture of limestone and finely divided clay in a furnace to a temperature high enough to drive off the carbonic acid gas.
- In 1845, Issac C. Johnson invented the cement by increasing the temperature at which the mixture of limestone and clay were burned to form clinker. This cement was the prototype of the modern Portland cement.
- From then onward, a gradual improvement in the properties and qualities of cement has been made possible by researchers in U.S.A., U.K., France and Germany
Cement Clinker
In the manufacture of Portland cement, clinker occurs as lumps or nodules, usually 3 millimeters (0.12 in) to 25 millimeters (0.98 in) in diameter, produced by sintering (fused together without melting to the point of liquefaction) limestone and alumino silicate materials such as clay during the cement kiln stage.
Today cement finds extensive use in all types of construction works; in structures where high strength is required e.g. bridge piers, light houses, lofty towers, and large structures such as bridges, silos, chimneys. And also in structures exposed to the action of water, e.g. reservoirs, dams, dock yards etc. Cement mortar, concrete, reinforced brick work, artificial stones, plastering, pointing and partition walls are routinely used in buildings.
