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Gypsum mortar is an ancient mortar used in construction. A component of Portland cement used to prevent flash setting (too rapid hardening) of concrete . A wood substitute in the ancient world: For example, when wood became scarce due to deforestation on Bronze Age Crete , gypsum was employed in building construction at locations where wood was ...
Lime mortar or torching [1] [2] is a masonry mortar composed of lime and an aggregate such as sand, mixed with water. It is one of the oldest known types of mortar, used in ancient Rome and Greece, when it largely replaced the clay and gypsum mortars common to ancient Egyptian construction. [3]
A cement is a binder, a chemical substance used for construction that sets, hardens, and adheres to other materials to bind them together. Cement is seldom used on its own, but rather to bind sand and gravel together. Cement mixed with fine aggregate produces mortar for masonry, or with sand and gravel, produces concrete. Concrete is the most ...
The mortar and pestle, with the Rod of Asclepius, the Green Cross, and others, is one of the most pervasive symbols of pharmacology. [10] For pharmaceutical use, the mortar and the head of the pestle are usually made of porcelain, while the handle of the pestle is made of wood. This is known as a Wedgwood mortar and pestle and originated in 1759.
Type S lime is almost always dolomitic lime, hydrated under heat and pressure in an autoclave, and used in mortar, render, stucco, and plaster. Type S lime is not considered reliable as a pure binder in mortar due to high burning temperatures during production. Kankar lime, a lime made from kankar which is a form of calcium carbonate.
The excavation of the underground aqueduct of Megara revealed that a reservoir was coated with a pozzolanic mortar 12 mm thick. This aqueduct dates back to c. 500 BCE. [9] Pozzolanic mortar is a lime based mortar, but is made with an additive of volcanic ash that allows it to be hardened underwater; thus it is known as hydraulic cement.
Some of the second raw materials used are: clay, shale, sand, iron ore, bauxite, fly ash and slag. Portland cement clinker is made by heating a homogeneous mixture of raw materials in a rotary kiln at high temperature. The products of the chemical reaction aggregate together at their sintering temperature, about 1,450 °C (2,640 °F).
Sorel cement (also known as magnesia cement or magnesium oxychloride) is a non-hydraulic cement first produced by the French chemist Stanislas Sorel in 1867. [1]In fact, in 1855, before working with magnesium compounds, Stanislas Sorel first developed a two-component cement by mixing zinc oxide powder with a solution of zinc chloride.