Portland cement was first manufactured by Joseph Aspin, bricklayer and builder. He received a patent for Portland cement on October 21, 1824.
Since then, there has been continuous effort in cement and he has discovered that the conversion of chemical compounds into cement reveal different characteristics and properties. For highly varied and high-demand cement conditions, the types of cement that can only be manufactured by varying the relative proportions of oxide compounds are not sufficient.
Tests have been conducted to add new materials to the cement known as additives, replacing the basic raw materials during grinding or cement preparation. The use of additives, the alteration of the chemical composition and the application of different raw materials resulted in the availability of many types of cement.
There are many types of cement besides ordinary Portland cement. The main types are briefly described below:
WHITE CEMENT
What Is White Cement? And Its Uses
The cement becomes white, without cement from the oxidation of iron, magnesium and chlorine. In the manufacture of this cement, petroleum is used in place of coal as fuel. White cement is used for floors finishing, plastering and decorative work.
White Cement Used In replacing glazed tile. It is used to repair marble and shiny tiles.
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COLOURED CEMENT
What Is Coloured Cement? And Its Uses
Cement of the desired colour is produced by closely mixing the pigments with ordinary cement. Chlorine oxide gives a green colour. Cobalt turns blue. Iron oxide with different proportions produce brown, red or yellow. The addition of manganese dioxide gives a black or brown cement
Coloured Cement Used In finishing touches to the floors, walls, window sills and roofs.
RAPID HARDENING CEMENT
What Is Rapid hardening cement? And Its Uses
This cement can be manufactured by increasing lime content and burning at high temperature while manufacturing cement. Grinding to very fine is also necessary. Though the initial and final setting time of this cement is the same as that of portland cement, it gains strength in the early days. This property helps in earlier removal of formworks and speed in construction activity.
Rapid Hardening Cement Used In
1. This can be used when construction has to be done fast.
2. When the shuttering of concrete has to be removed soon.
3. light in weight.
4. It is not easily damaged.
5. Structural members built from this cement can be preloaded.
6. This cement requires short-term treatment.
7. This allows more permissible stresses in the design.
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QUICK-SETTING CEMENT
What Is quick-setting cement? And Its Uses
Quick-setting is done adding a small amount of aluminium sulphate and reducing the percentage of gypsum during the preparation of this cement. The precision grinding adds to the quick setting property. The cement begins to set within 5 minutes of adding water and becomes a hard in 30 minutes.
Quick-Setting Cement Used In the place concrete under regular or slow running water.
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LOW HEAT CEMENT
What Is Low Heat Cement? And Its Uses
It is a type of Portland cement that hardens and sets the process of the very low heat of hydration. in these, the lowest percentage is tricalcium aluminate, about 3 to 5 per cent, and the highest percentage of dicalcium silicate, about 40 to 45 per cent.
Low Heat Cement Used In dam construction because it reduces the development of cracks in the structure.
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LCETED TRIVIA
What Is Heat Hydration?
The heat of hydration is the heat generated during the chemical reaction between cement and water. In the case of mass concrete, such as the construction of dams, this heat produced will be greater, and it will affect the stability of the structure. Therefore, there is a need to control the amount of heat produced and the use of this type of cement
POZZOLANA CEMENT
What Is Pozzolana Cement? And Its Uses
Pozzolana is a volcanic power. It can be processed from shales and some kind of clay. This cement contains pozzolana material is 10 to 30 per cent. This will counter the action of sulphate. It releases less heat during setup. This provides greater water tightness. Its tensile strength is high but compression strength is low.
Pozzolana Cement Used In mass concrete works. It is also used in sewer line works.
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EXPANDING CEMENT
What Is Expanding Cement? And Its Uses
This cement expands when sets. This property is achieved by adding an expanding medium such as sulfoaluminate and a stabilizing agent in ordinary cement.
Expanding Cement Used In filling cracks in concrete structures.
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HIGH ALUMINA CEMENT
What Is High Alumina Cement? And Its Uses
It is made by calcining a mixture of lime and bauxite. It is highly resistant to sulfate and acid attack. This creates almost full strength within 24 hours of adding water.
High Alumina Cement Used In under waterworks.
Advantages Of High Alumina Cement
a. It is very resistant to being hit by seawater.
b. It hardens quickly.
c. It does not expand when set.
d. It can stand at very high temperatures.
e. It resists the act of freezing.
Disadvantages Of High Alumina Cement
a. It cannot be used for heavy concrete works.
b. It is very expensive.
c. Care should be taken to avoid contact with ordinary cement or lime as it reduces strength.
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BLAST FURNACE SLAG CEMENT
What Is Blast Furnace Slag Cement? And Its Uses
The iron and steel industry produces large-scale blast furnace slag as a byproduct. Slag is a waste product of pig iron, and it contains the basic components of cement-like alumina, limestone, and silica.
By grinding clinkers of cement with about 60 to 65 per cent of slag. This cement has a slow hardening rate and low heat of hydration. Its strength is low in the early days and, therefore, requires a long healing period.
Blast Furnace Slag Cement Used In marine structures because It is not affected by seawater.
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ACID RESISTANT CEMENT
What Is Acid Resistant Cement? And Its Uses
This cement is made by adding anti-acid aggregates such as quartz, quartzite, sodium silicate. This cement has good resistance to acid and water activity.
Acid Resistant Cement Used In the construction of chemical plants.
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SULPHATE RESISTANT CEMENT
What Is Sulphate Resistant Cement? And Its Uses
This cement is manufactured by keeping the percentage of tricalcium aluminate C3A less than five per cent of ordinary cement.
Sulphate Resistant Cement Used In the construction of structures that are damaged by alkaline conditions. Examples of such structures are canals and inscriptions.
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FLY ASH BLENDED CEMENT
What Is Fly Ash Blended Cement? And Its Uses
Fly ash is produced from thermal stations. The particles of fly ash are very minute and they are in the air and create air pollution. Thermal power plants have to spend a lot of money to dispose of it.
A great way to get rid of fly ash is to mix it with cement in a confined state and get some beneficial effects on the cement. Nowadays, cement factories produce fly ash at their own heat stations or borrow it from other heat stations and process it further to make it more compatible with cement. 20 to 30% flyash is used to blend.
Fly Ash Blended Cement Used Have the superior quality of resistance to weathering action
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