17 types of cement, properties and uses in construction described here. Each type of cement has different properties, use for concrete with any grade of concrete and its chemical composition.
17 Types of Cement
- Ordinary Portland Cement (OPC)
- Portland Pozzolana Cement (PPC)
- Portland Slag Cement (PSC)
- Rapid Hardening Cement
- Ultra Rapid Hardening Cement
- Quick setting Cement
- Low Heat Portland Cement
- Sulphate resisting Cement
- Blast Furnace Slag Cement
- High Alumina Cement
- White Cement
- Colored Cement
- Air Entraining Cement
- Expansive Cement
- Hydrophobic Cement
- Low Alkali Cement
- Water Proof Portland Cement
1. Ordinary Portland Cement Properties and Use
In 17 types of cement, Ordinary portland cement is on the top because of its huge uses and quality.
Ordinary portland cement is manufactured by proper mixing calcareous and argillaceous materials together by burning at a clinkering temperature and grinding the resultant clinker so as to produce a cement capable of compiling the chemical and physical requirement given in IS 269-1976.
After burning the only gypsum is added to cement up to 3% to 4% in order to increase the setting time of the cement.
The ordinary Portland cement or OPC is produced and used in far larger quantities than all the other types of cement all over the world. It is well suited for use in general concrete construction where there is no exposure to sulfates as it has low sulfates resistance also it should not be used to construct massive structures like dams so as to avoid temperature or shrinkage cracks.
Weight and Volume
The weight of one bag of OPC is 50 kg and its volume is 35 liter or 0.035 cum. One cubic meter of OPC contains 28.8 bags.
The ordinary Portland cement or OPC is also called as normal setting cement.
Chemical Composition of Ordinary Portland Cement
The chemical requirement of the OPC is
- The ratio of the percentage of lime to percentage of silica, aluminium and iron oxide should not be greater than 1.02 and not less than 0.66.
- The ratio of the percentage of aluminium to that of iron oxide should not be less than 0.66.
- Percentage of the insoluble residue by mass should be more than 6%.
- Percentage of magnesia by mass should not be more than three percent and total loss on ignition should not be more than five percent.
Physical Requirement in This Type of Cement
The physical requirement of the OPC are
- When tested for fineness by Blaine’s air permeability method, the OPC should have minimum specific surface area of 22.50 cm2 per gram or when tested for fineness by seiving on 90 micron IS sieve, the residue on the sieve shall not be more than 10%.
- When tested for soundness by le-chatelier method the expansion should not be more than 10 mm or when tested for soundness by Autoclave test, the expansion should not be more than 0.8%.
- When tested for setting time by Vicat apparatus, the initial setting time should not be less than 30 minutes and the final setting time should not be more than 600 minutes.
- When tested for compressive strength as per IS 4031 – 1968, the 28 days compressive strength of OPC 33, 43 and 53 grade shall be simultaneously 33, 43 and 53 N/mm2 or MPa.
2. Portland Pozzolana Cement
In this type of cement, Pozzolana burnt clay, shale or fly ash mainly containing siliceous mineral substances the pozzolana have not cementing value themselves but they have the priority of combining with free lime present in OPC to produce a stable lime pozzolana compound which has definite cementitious properties.
Thus the free lime present in OPC which is readily subjected to chemical attack is thus removed by the pozzolana and is used for attaining strength. The pozzolana that to be blended for producing portland pozzolana cement shall conform IS 1727-1967 regarding fineness and lime reactivity that the portland pozzolana cement product is equivalents to OPC.
The portland pozzolana is manufactured either by intergrading portland cement clinker and pozzolana ( 10% to 25%) or by intimately and uniformly blending ordinary portland cement and fine pozzolana.
3. Portland Slag Cement
Earlier this cement was called as portland blast furnace slag cement because in those days the granulated slag obtained only from the blast furnaces was used to produce this cement. Now the slag obtained from other types of furnace slag cement but having identical properties as those of granulated blast furnace slag can also be used for the manufacture of this cement as per IS 455-1976 and therefore now this cement is called portland slag cement.
Blast furnace slag cement is a waste product in the manufacture of pig iron and it is a mixture of lime, silica, and alumina. The molten slag is rapidly chilled or quenched in water or stream and air in order to get the granulated slag.
Manufacturing of Portland slag cement
The manufacture of portland slag cement has been developed primarily to utilize blast furnace slag a waste product from blast furnaces.
Thus the output of cement production in our country will considerably increase and the cement can be available at an economical price due to the profitable use and otherwise waste product namely the blast furnace slag.
Therefore we must try to manufacture and use the Portland slag cement in as large quantities a possible.
4. Rapid Hardening Cement
Rapid hardening cement is very likely to ordinary portland cement (OPC). This (Rapid hardening) cement contains higher tri-calcium silicate ( C3S ) content and finer grinding. Therefore it gives greater compressive strength development at an early stage than ordinary portland cement. The compressive strength of this cement at the age of 3 days is almost same as the 7 days strength of ordinary portland cement with the same water-cement ratio.
The advantage of using this cement is form work can be removed earlier and reused in other areas which save the time and cost of form work. Rapid hardening cement can be used in prefabricated concrete construction, road works etc.
5. Ultra Rapid Hardening Cement
Slump loss of the ultra rapid hardening polymer modified concretes rapid at higher fiber content
and polymer –cement ratio.
Regardless of the fiber content, the water absorption of the ultra rapid-hardening polymer modified concretes tend to decrease with increasing polymer-cement ratio.
Except for a few cases, the flexural and tensile strengths of ultra rapid-hardening polymer modified concretes tend to increase with increasing fiber content, and to reach maximum at a fiber content of 0.15%. The strengths are inclined to increase with an increase in the polymer binder ratio.
Ultra rapid-hardening polymer-modified concretes with higher polymer-cement ratio provide
higher flexural and tensile strengths than unmodified concretes
6. Quick Setting Cement
Quick setting cement shall be used where the setting time of the cement is to be less and hardening of cement to be fast. The cement clinkers are grinded with aluminium sulphate Al2(So4)3, which accelerates the initial and final setting time of cement. aluminium sulphate Al2(So4)3 is used as accelerating admixture in the dosage range of 1% to 3% by weight of cement clinkers .
Quick setting cement is used in under water construction. It is also used in rainy & cold weather conditions and Where, quick strength is needed in short span of time.
7. Low Heat Portland Cement
A considerable quantity of heat is produce during the chemical reaction that takes place between cement and water during the sitting and hardening of cement.
In the case of ordinary structures, the generated heat gets lost by dissipation from the surface of the member and hence it cannot produce any harmful effects.
However, in case of mass concrete work such as dams, retaining walls, bridge abutments etc.
The heat of hydration generated by the use of ordinary portland cement proves dangerous. In such case, the rate of loss of heat from the surface of the structure is much lower than the build up of heat inside the concrete mass, this results in setting up tensile stresses during curing of the concrete and finally leads to cracking of he concrete mass.
The cracked concrete is structurally useless and is difficult to rectify. One of the ways to prevent the build-up of heat in mass concrete is to use the low heat portland cement.
The manufacturing process of the low heat portland cement is similar to that of the ordinary portland cement.
As the name suggests, the low heat portland cement gives out less heat of hydration and also gains strength at a slower rate, but C3A2 which produce more heat of hydration is kept lower and the percentage of cement compounds like C2S and C4AF, which produce less heat of hydration is kept higher.
The low heat portland cement should satisfy the chemical and physical requirements given is IS 269-1976. This cement is available only on special orders and hence it is costly and therefore it is not used for ordinary concrete weather concreting.
This cement gives greater sulphates resistance than OPC and it is used invariably for massive concrete works to avoid temperature cracks or shrinkage cracks produced due to excessive heat of hydration.
8. Sulphate Resisting Cement
Sulfate resisting cement is made by reducing C3A and C4AF content. Cement with this composition has excellent resistance to sulphate attack. Sulphate resisting cement is used in the construction of foundation in soil where subsoil contains very high proportions of sulphate.
9. Blast Furnace Slag Cement
When it comes to Blast furnace slag cement, the normal cement clinkers are mixed with up to 65% of the blast furnace slag for the final grinding. Blast furnace slag cement can be used with advantage in mass concrete work like dams, foundations, and abutments of bridges, retaining walls , construction in sea water.
10. High Alumina Cement
This (High alumina) cement is a special cement, manufactured by mixing of bauxite ( aluminum ore) and lime at a certain temperature. High alumina cement is also known as calcium aluminium cement. The compressive strength of High alumina cement is very high and more workable than ordinary portland cement.
11. White Cement
This cement is a type of ordinary Portland Cement which is pure white in color and has practically the same composition and same strength as ordinary portland cement. To obtain the white color in cement, iron oxide content is considerably reduced. The raw materials used in this cement are limestone and china clay.
This cement, due to its white color, is mainly used for interior and exterior decorative work like external renderings of buildings, facing slabs, floorings, ornamental concrete products, paths of gardens, swimming pools etc.
12. Colored Cement
Colored cement is a type of cement which produced by adding 5 to 10% mineral pigments with portland cement during the time of grinding. Due to the various color combinations this cement is mainly used for interior and exterior decorative works for buildings etc.
13. Air Entraining Cement
Air entraining cement is produced by air entraining agents such as resins, glues, sodium salts of sulfate with ordinary portland cement ( OPC ).
14. Expansive Cement
This type of cement (Expansive cement) does not shrink during and after the time of hardening but expands slightly with time. Expansive cement is mainly used for grouting anchor bolts and pre-stressed concrete ducts.
15. Hydrophobic Cement
This type of cement (Hydrophobic cement) is manufactured by adding water repellent chemicals to ordinary portland cement in the process of grinding. Stored hydrophobic cement does not spoiled even during monsoon. Hydrophobic cement is claimed to remain unaffected when transported during rains also. This cement is mainly used for the construction of water structures such dams, water tanks, spillways, water retaining structures etc.
16. Low Alkali Cement
Low-alkali cements are portland cements with a total content of alkalies not above 0.6 percent. Low alkali cement is used in concrete made with certain types of aggregates that contain a form of silica that reacts with alkalies to cause an expansion that can disrupt a concrete.
17. Water Proof Portland Cement
This cement is prepared by mixing with ordinary portland cement or rapid hardening cement, a small percentage of some metal stearates (Ca, Al, etc) at the time of grinding. Water proof portland cement is used for the construction of water-retaining structure like tanks, reservoirs, retaining walls, swimming pools, dams, bridges, piers etc.
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