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The method of making cement from limestone (CaCO 3) and low-silica bauxite (Al 2 O 3) was patented in France in 1908 by Bied of the Pavin de Lafarge Company. The initial development was as a result of the search for a cement offering sulfate resistance. The cement was known as "Ciment fondu" and "Ciment électro-fondu" in French. [2] [3]
This template has been created for transclusion in the articles Concrete, Cement, and Silica fume. It replaces the file at right. That file had been tagged for translation to SVG format, as if it were a graphic. But since it is really a table, I have re-rendered it in wiki markup.
A mix is then designed using cement (Portland or other cementitious material), coarse and fine aggregates, water and chemical admixtures. The method of mixing will also be specified, as well as conditions that it may be used in. This allows a user of the concrete to be confident that the structure will perform properly.
In atmospheric chemistry, mixing ratio usually refers to the mole ratio r i, which is defined as the amount of a constituent n i divided by the total amount of all other constituents in a mixture: = The mole ratio is also called amount ratio. [2]
This slurry is further mixed with a synthetic aerated foam in a concrete mixing plant. [9] The foam is created using a foaming agent, mixed with water and air from a generator. The foaming agent must be able to produce air bubbles with a high level of stability, resistant to the physical and chemical processes of mixing, placing, and hardening.
Cement chemist notation (CCN) was developed to simplify the formulas cement chemists use on a daily basis. It is a shorthand way of writing the chemical formula of oxides of calcium , silicon , and various metals .
The water-cement ratio of the fresh concrete mix is one of the main, if not the most important, factors determining the quality and properties of hardened concrete, as it directly affects the concrete porosity, and a good concrete is always a concrete as compact and as dense as possible.
Portland cement is usually made from cheap, quarried raw materials, and these usually contain substantial amounts of Cr, Mn and Fe. For example, limestones used in cement manufacture usually contain 0.3-1% Fe 2 O 3, whereas levels below 0.1% are sought in limestones for white manufacture. Typical clays used in gray cement rawmix may contain 5 ...