◆Type of Cements◆
ii. Rapid Hardening Cement – IS: 8041-1990
iii. Extra Rapid Hardening Cement
iv. Low Heat Portland cement - IS: 12600-1989
v. Portland Slag Cement – IS: 455-1989
vi. Portland Pozzolana Cement – IS: 1489-1991
(Part 1 and 2)
vii. Sulphate Resisting Portland Cement – IS:
12330-1988
viii. White Portland Cement – IS: 8042-1989
ix. Coloured Portland Cement - IS: 8042-1989
x. Hydrophobic Cement - IS: 8043-1991
xi. High Alumina Cement - IS: 6452-1989
xii. Super Sulphated Cement - IS: 6909-1990
xiii. Special Cements
a. Masonry Cement
b. Air Entraining Cement
c. Expansive Cement
d. Oil Well Cement
In addition to ordinary portland cement there are
many varieties of cement. Important varieties are
briefly explained below:
(i) White Cement: The cement when made free
from colouring oxides of iron, maganese and
chlorium results into white cement. In the
manufacture of this cement, the oil fuel is used
instead of coal for burning. White cement is used
for the floor finishes, plastering, ornamental works
etc. In swimming pools white cement is used to
replace glazed tiles. It is used for fixing marbles
and glazed tiles.
(ii) Coloured Cement: The cements of desired
colours are produced by intimately mixing
pigments with ordinary cement. The chlorium
oxide gives green colour. Cobalt produce blue
colour. Iron oxide with different proportion
produce brown, red or yellow colour. Addition of
manganese dioxide gives black or brown coloured
cement. These cements are used for giving
finishing touches to floors, walls, window sills,
roofs etc.
(iii) Quick Setting Cement: Quick setting cement
is produced by reducing the percentage of gypsum and adding a small amount of aluminium sulphate
during the manufacture of cement. Finer grinding
also adds to quick setting property. This cement
starts setting within 5 minutes after adding water
and becomes hard mass within 30 minutes. This
cement is used to lay concrete under static or slowly running water.
(iv) Rapid Hardening Cement: This cement can be
produced 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 early days. This property helps in earlier removal of form works and speed in construction activity.
(v) Low Heat Cement: In mass concrete works like
construction of dams, heat produced due to
hydration of cement will not get dispersed easily.
This may give rise to cracks. Hence in such
constructions, it is preferable to use low heat
cement. This cement contains low percentage (5%) of tricalcium aluminate (𝐶3𝐴) and higher
percentage (46%) of dicalcium silicate (𝐶2𝑆).
(vi) Pozzolana Cement: Pozzolana is a volcanic
power found in Italy. It can be processed from
shales and certain types of clay also. In this cement pozzolana material is 10 to 30 per cent. It can
resist action of sulphate. It releases less heat during setting. It imparts higher degree of water tightness.
Its tensile strength is high but compressive strength is low. It is used for mass concrete works. It is also used in sewage line works.
(vii) Expanding Cement: This cement expands as
it sets. This property is achieved by adding
expanding medium like sulpho aluminate and a
stabilizing agent to ordinary cement. This is used
for filling the cracks in concrete structures.
(viii) High Alumina Cement: It is manufactured by
calcining a mixture of lime and bauxite. It is more
resistant to sulphate and acid attack. It develops
almost full strength within 24 hours of adding
water. It is used for under water works.
(ix) Blast Furnace Cement: In the manufacture of
pig iron, slag comes out as a waste product. By
grinding clinkers of cement with about 60 to 65
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