TYPES OF CEMENT AND THEIR USES
TYPES OF CEMENT AND THEIR USES
Cement is a hydraulic binder,
i.e. a finely ground inorganic material which, when mixed with water, forms
a paste which sets and hardens by means of hydration reactions and processes
and which, after
hardening, retains its strength and stability even under water.
There are various types of cement used in
construction projects. Each type of cement has its own properties which are
caused by composition materials used during its manufacture. Difference in
cement properties causes the cement to have different uses and advantages.
The
following are 13 types of cement and their uses and their brief descriptions.
- Ordinary Portland Cement (OPC)
Ordinary Portland cement is most widely produced and used
type of cement which is suitable for all general construction purposes such as
brick works, plaster works and or usual concrete works.
- Portland Pozzolana Cement (PPC)
This cement has
high resistance to various chemical attacks on concrete compared with ordinary
Portland cement and thus it is widely used. It is used in marine structures,
for laying concrete under water such as bridges, piers, dams and mass concrete works etc.
As it gives a better surface finish, it is used in decorative
and art structures, it is also used in the manufacture of precast sewage pipes
- Rapid Hardening Cement
Rapid Hardening Cement comes when OPC is mixed
with high content of lime and Tri-calcium silicate (C3S) which cause it to gain
strength more quickly compared to OPC.
The strength gained by Rapid Hardening Cement
at 3 days is similar to that gained by OPC at 7 days at the same water-cement
ratio.
Advantage of this type of cement is reduction
of construction cost by increasing rate of construction in formwork reusing. Rapid
hardening cement is used in prefabricated concrete construction, road works,
etc
- Quick setting cement
Quick setting cement
is one which sets in a very short time, the difference between the quick setting cement
and rapid hardening cement is that quick setting cement sets earlier while rate
of gain of strength is similar to Ordinary Portland Cement, while rapid
hardening cement gains strength quickly. Formworks in both cases can be removed
earlier.
Quick setting cement is used where works is to
be completed in very short period and for concreting in static or running water.
- Low Heat Cement
It is a type of cement which produces low heat
of hydration during setting, and thus is used in mass concrete construction
like gravity dams, as the low heat of hydration prevents the cracking of
concrete due to heat.
- Sulphates resisting cement
Sulfate resisting cement is used to reduce the
risk of sulphate attack on concrete and thus is used in construction of
foundations where soil has high sulphate content.
It is used for construction work near seashore or
where sulphate content is higher in ground water
- High Alumina Cement
High
Alumina cement is obtained by mixing bauxite and ordinary lime with clinker
during the manufacture of OPC, it is a rapid hardening cement with initial
setting time of 3.5 hours and final setting time 5 hours.
- White Cement
It is a type of ordinary Portland cement
which is white in color, it is used for joining marbles and ceramic tiles, for preparing joints of
sanitary wares, architectural works such as precast
curtain wall and facing panels, terrazzo surface and also It is used in manufacturing of mosaic
tiles.
- Coloured cement
Coloured
cement is produced when OPC is mixed by 5 – 10 percent of mineral pigment of
certain desired colour. They are widely used for decorative works in floors.
- Air Entraining Cement
Air-entraining
cement is a type of cement which entrains tinny air bubbles in concrete, this
type of cement is produced by adding indigenous air entraining agents such as
resins, glues etc. during the grinding of clinker.
This type of cement is especially suited
to improve the workability with smaller water cement ratio and to improve frost
resistance of concrete
- Expansive cement
Expansive cement expands slightly with
time during hydration and does not shrink during and after the time of
hardening. This cement is mainly used for grouting anchor bolts and
prestressed concrete ducts.
Comments
Post a Comment