Remember me in your pray

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Assala mu alykum My Name is saqib imran and I am the
student of b.tech (civil) in sarhad univeristy of
science and technology peshawer.
I have written this notes by different websites and
some by self and prepare it for the student and also
for engineer who work on field to get some knowledge
from it.
I hope you all students may like it.
Remember me in your pray, allah bless me and all of
you friends.
If u have any confusion in this notes contact me on my
gmail id: Saqibimran43@gmail.com
or text me on 0341-7549889.
Saqib imran.

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Bricks
Bricks are the small rectangular blocks typically made of fired or sun-dried clay, typically used in
building. The bricks are obtained by moulding clay in rectangular blocks of uniform size and then
by drying and burning these blocks. As bricks are of uniform size, they can be properly arranged
and further, as they are light in weight, no lifting appliance is required to them. The bricks don’t
require dressing and the art of laying bricks is so simple that the brickwork can be carried out with
the help of unskilled labours. Thus, at places where stones are not easily available, but if plenty of
clay suitable for the manufacturing of bricks, the bricks replace stones.
The common brick is one of the oldest building materials and it is extensively used at present as a
leading material of construction because of its durability, strength, reliability, low cost, easy
availability, etc.
Contents:
 History
 Brickwork vs Stonework
 Composition
 Harmful Ingredients
 Qualities
 Strength
History of Bricks
The bricks seem to have been produced since the dawn of the civilization in the sun-dried form.
The Great Wall of China (210 B.C.) was built with both, burnt and sun-dried bricks. The other
examples of the use of bricks in early stage of civilization could be cited in Rome and other places.

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The medieval cities were of wood and because of the disastrous fire potential of wood; the bricks
replaced the wood over the years. For instance, the great fire of London in 1666 changed London
from being a city of wood to one of brick. A number of country farm houses still exists in Great
Britain and profess to be monuments of the excellent hand-made bricks.
The bricks have been used all over the world in every class and kind of building. If the total bricks
produced till today are to be counted, the figure would indeed be astronomical. It is understood
that about 65 percent of the bricks in world goes into dwellings and the balance into commercial,
industrial and institutional buildings.
The bricks have established as an age old material right from the thatched house to the multi-
storeyed buildings. They were initially handmade and used as load bearing material for various
structures. With the passage of time and advent of cement and steel, the frames only are filled up
with the burnt clay bricks. The production of burnt clay bricks on a scientific and modern basis
including proper mining of clays can lead to availability of quality bricks.
In India, the process of brick making has not changed since many centuries except some minor
refinements. There have been hardly any efforts in the country to improve the brick-making
process for enhancing the quality of bricks. The main reason for this attitude is that the production
of bricks has been largely remained confined to the unorganized small sector. Some of the large
mechanized brick plants came up in the past but they failed for some reason or other. The result is
that the construction industry is largely dependent on the small sector which is unable to deliver
high quality bricks in view of rising fuel cost, outdated technology and lower efficiency of
production.
Brickwork vs Stonework
The brickwork is superior to the stonework in the following respects.
1. At places where stones are not easily available but where there is plenty of clay, the
brickwork becomes cheaper than stonework.
2. The cost of construction works out to be less in case of brickwork than stonework as less
skilled labour is required in the construction of brickwork.
3. No complicated lifting devices are necessary to carry bricks as they can be easily moved
by manual labour.
4. The bricks resist fire better than stone and hence, in case of a fire, they don’t easily
disintegrate.
5. The bricks of good quality resist the various atmospheric effects in a better way than the
stones.
6. In case of brickwork, the mortar joints are thin and hence the structure becomes more
durable.
7. It is easy to construct connections and openings in case of brickwork than stonework.
The brickwork is inferior to the stonework in the following respects:

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1. The brickwork is less watertight than stonework. The bricks absorb moisture from the
atmosphere and dampness can enter the building.
2. The brickwork doesn’t create a solid appearance in relation to the stonework and hence,
for public buildings and monumental structures, the stonework is found to be more useful
than brickwork.
3. The stonework is stronger than brickwork.
4. The architectural effects of better quality can be developed by the stonework.
5. The stonework is cheaper at places where stones are easily available.
Composition of good brick material
Following are the constituents of good brick material:
 Alumina: It is the chief constituent of every kind of clay. A good brick should contain
20% to 30% of alumina. This constituent imparts plasticity to the clay so that it can be
moulded. If alumina is present in excess, with inadequate quantity of sand, the raw bricks
shrink and warp during drying /burning and become too hard when burnt.
 Silica: It exists in clay either as free or combined. As free sand, it is mechanically mixed
with clay. In combine form, it exists in chemical composition with alumina. A good brick
material should contain about 50% to 60% of silica. The presence of this constituent
prevents cracking, shrinking and warping of raw bricks. It thus imparts uniform shape to
the bricks. The durability of bricks depends on the proper proportion of silica in brick
material. The excess of silica destroys the cohesion between particles and the bricks
become brittle.
 Lime: A small quantity of lime not exceeding 5 percent is desirable in good brick material.
It should be present in a very finely powdered state because even small particles of the size
of a pin-head cause flaking of the bricks. The lime prevents shrinkage of raw bricks. The
sand alone is infusible. But it slightly fuses at kiln temperature in presence of lime. Such
fused sand works as a hard cementing material for brick particles. The excess of lime causes
the brick to melt and hence its shape is lost. The lumps of lime are converted into quick
lime after burning and this quick lime slakes and expands in presence of moisture. Such an
action results in splitting of bricks into pieces.
 Oxide of iron: A small quantity of oxide of iron to the extent of about 5 to 6 percent is
desirable in good brick material. It helps as lime to fuse sand. It also imparts red colour to
the bricks. The excess of oxide of iron makes the bricks dark blue or blackish. If, on the
other hand, the quantity of iron oxide is comparatively less, the bricks will be yellowish in
colour.
 Magnesia: A small quantity of magnesia in brick material imparts yellow tint to the bricks
and decreases shrinkage. However, excess of magnesia leads to the decay of bricks.
Harmful ingredients in brick material
Following are the ingredients which are undesirable in the brick material:
 Lime: The excess of lime is undesirable in brick material.

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 Iron pyrites: If iron pyrites are present in brick material, the bricks are crystallized and
disintegrated during burning because of the oxidation of the iron pyrites.
 Alkalies: These are mainly in the form of soda and potash. The alkalies act as a flux in the
kiln during burning and they cause bricks to fuse, twist and warp. As a result, the bricks
are melted and they loose their shape. Further, the alkalies remaining in bricks will absorb
moisture from the atmosphere, when bricks are used in masonry. Such moisture, when
evaporated, leaves behind grey or white deposits on the wall surface. The appearance of
the building as a whole is then seriously spoiled.
 Pebbles: The presence of pebbles or grits of any kind is undesirable in brick material
because it will not allow the clay to be mixed uniformly and thoroughly which will result
in weak and porous bricks. Also, the brick containing pebbles will not break regularly as
desired.
 Vegetation and organic matter: The presence of vegetation and organic matter in brick
material assists in burning. But if such matter is not completely burnt, the bricks become
porous. This is due to the fact that the gases will be evolved during the burning of the
carbonaceous matter and it will result in the formation of small pores. Hence, it is necessary
to see that all these gases are removed during the process of burning for getting bricks of
good quality.
Qualities of good bricks
The good bricks which are to be used for the construction of important structures should posses
the following qualities:
1. The bricks should be table-mounted, well burnt in kilns, copper-coloured, free from cracks
and with sharp & square edges. The colour should be uniform and bright.
2. The bricks should be uniform in shape and should be of standard size.
3. The bricks should give a clear metallic ringing sound when struck with each other.
4. The bricks when broken or fractured should show a bright homogeneous and uniform
compact structure free from voids.
5. The bricks shouldn’t absorb water more than 20 percent by weight for first class bricks and
22 percent by weight for second class bricks, when soaked in cold water for a period of 24
hours.
6. The bricks should be sufficiently hard. No impression should be left on brick surface, when
it is scratched with finger nail.
7. The bricks should not break into pieces when dropped flat on hard ground from a height of
about one meter.
8. The bricks should have low thermal conductivity and they should be sound-proof.
9. The bricks, when soaked in water for 24 hours, should not show deposits of white salts
when allowed to dry in shade.
10. No brick should have the crushing strength below 5.5 N/mm2
.
Strength of bricks
Following factors affect the strength of bricks:

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1. Composition brick making material
2. Preparation of clay and blending of ingredients
3. Nature of moulding adopted
4. Care taken in drying and stacking of raw or green bricks
5. Type of kiln used including type of fuel and its feeding
6. Burning and cooling processes
7. Care taken in unloading
It is thus obvious that not only the bricks of different brick fields will have different strengths, but
in the same brick field, the bricks of the same batch may have different strengths.
The average crushing strength and tensile strength of hand moulded bricks are 60,000 kN/m2
and
2000 kN/m2
respectively. The shearing strength of bricks is about one-tenth of the crushing
strength. In practice, however, the bricks are not subjected to the tensile stresses.
It may be noted that the strength of brickwork mainly depends on the type of mortar used and not
so much on the individual strength of the bricks.
Standard Brick Size
Various countries have various standard brick size and dimensions, however, brick can be made
in multiple shapes and sizes, depending on its application. If bricks are large, it is difficult to burn
them properly and they become too heavy to be placed with a single hand. On the other hand, if
bricks are small, more quantity of mortar is required. Hence, a standard dimension is determined
for various brick works. Actual size (or the specified size), is the real dimension of the
brick. Nominal size is the actual size plus the width of the mortar joint. Most bricks are
manufactured in such a way that the nominal sizes fit into a grid of 4 inch, which comply with the
modules of other building materials such as doors, windows, and wood components.

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Contents:
 Brick Size in England
 Brick Size in USA
 Brick Size in Australia
 Brick Size in India
 Brick Size in Nepal
 Face Brick Dimensions
Standard Brick Size in England
“In England, the length and width of the common brick has remained fairly constant over the
centuries but the depth has varied from about two inches (about 51 mm) or smaller in earlier times
to about two and a half inches (about 64 mm) more recently. In the United Kingdom, the usual
size of a modern brick is 215 × 102.5 × 65 mm (about 8 5
⁄8 × 4 1
⁄8 × 2 5
⁄8 inches), which, with a
nominal 10 mm (3
⁄8 inch) mortar joint, forms a unit size of 225 × 112.5 × 75 mm (9 × 4 1
⁄2 ×
3 inches), for a ratio of 6:3:2.” – Wikipedia
Standard Brick Size in United States
“In the United States, modern standard bricks are (controlled by American Society for Testing and
Materials i.e. ASTM) about 8 × 3 5
⁄8 × 2 1
⁄4 inches (203 × 92 × 57 mm). The more commonly used
is the modular brick 7 5
⁄8 × 3 5
⁄8 × 2 1
⁄4 inches (194 × 92 × 57 mm). This modular brick of 7 5
⁄8 with
a 3
⁄8 mortar joint eases the calculation of the number of bricks in a given run.” – Wikipedia
Standard Brick Size in Australia
According to Boral Company in Australia, the standard brick size (or the working size) is 76mm
high, 230mm long and 110mm wide as per the Australian Standard AS4455. Some bricks are made
with different work sizes. 50 mm and 90 mm high bricks, 90 mm wide bricks and 290 mm long
bricks are used for different structural and aesthetic effect. Larger bricks are often used for more
economical laying and as a design feature either on their own or combined with smaller bricks.
In cyclonic areas larger (140 mm wide x 90 mm high x 290 mm long) hollow bricks are used to
allow reinforcement and grouting in the wall. Wider (150 mm wide) bricks can also be used in
walls requiring lower sound transmission, higher fire resistance levels and higher load bearing
capacity depending on the specific brick properties.
Standard & Nominal Brick size in India
In India, standard brick size is 190 mm x 90 mm x 90 mm as per the recommendation of BIS.
With mortar thickness, the dimension of the brick becomes 200 mm x 100 mm x 100 mm which
is also known as the nominal size of the modular brick.
Standard Brick Size in Nepal

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According to National Building Code (NBC 205 : 1994) of Nepal, the bricks shall be of a standard
rectangular shape, burnt red, hand-formed or machine-made, and of crushing strength not less than
3.5 N/mm². The higher the density and the strength, the better they will be. The standard brick size
of 240 x 115 x 57 mm with 10 mm thick horizontal and vertical mortar joints is preferable.
Tolerances of -10 mm on length, -5 mm on width and ±3 mm on thickness shall be acceptable for
the purpose of thick walls in this Mandatory Rules of Thumb (MRT).
Note: The main objective of these Mandatory Rules of Thumb (MRT) in National Building Code
of Nepal are to provide ready-to-use dimensions and details for various structural and non-
structural elements for up to three-storey reinforced concrete (RC), framed, ordinary residential
buildings commonly being built by owner-builders in Nepal.
Face brick dimensions:
Face bricks are the bricks used on exterior surfaces of a structure or houses. In the table below, we
have given the standard dimensions of face brick on various countries listed in alphabetical order
(both in imperial and metric unit).
Face brick (“house brick”) dimensions:
Standard Imperial (in) Metric (mm)
Australia 9 × 4⅓ × 3 230 × 110 × 76
Denmark 9 × 4¼ × 2¼ 228 × 108 × 54
Germany 9 × 4¼ × 2¾ 240 × 115 × 71
India 9 × 4¼ × 2¾ 228 × 107 × 69
Romania 9 × 4¼ × 2½ 240 × 115 × 63
Russia 10 × 4¾ × 2½ 250 × 120 × 65
South Africa 8¾ × 4 × 3 222 × 106 × 73
Sweden 10 × 4¾ × 2½ 250 × 120 × 62
United Kingdom 8½ × 4 × 2½ 215 × 102.5 × 65
United States 7⅝ × 3⅝ × 2¼ 194 × 92 × 57
Brick Veneer

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Brick veneer is a non-structural layer of brick used in construction of buildings, placed at outer
layer, generally backed by an air space. The materials used in brick masonry work and that in brick
veneer are same, however, they differ in the construction technique used while placing bricks. In
case of brick veneer, inner layer may be that of wood, metal or concrete. Before we move into the
topic, it is necessary to understand the fine difference between Brick veneer and brick masonry
work.
Contents:
 Stone Brick Vs Brick Veneer
 Advantages
 How to install
Stone Brick vs Brick veneer
The basic difference is that in house built of stone brick wall, brick or stone wall supports the
structural loading. While in case of brick veneer, it doesn’t support loading of house. It is usually
applied for decorative purposes. If you remove the brick veneer from the wall in the house, the
house will continue to stand still without falling down. In case of stone brick house, the structure
will fail if you take out the bricks or masonry from the wall.
In case of stone/masonry two layers of brick or stone is applied for constructing the wall. In case
of brick veneer, single layer of wall (external) is constructed using brick. While inner layer is
constructed using wood, metal, stone or concrete blocks. Undoubtedly, stone walls are stronger;
however, brick veneer walls are strong enough and better insulated.
Advantages of Brick Veneer

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Following are the advantages of brick veneer:
1. It is relatively easy to install and can be completed in shorter span of time.
2. Less man-force or labour is required.
3. The brick veneer walls have less weight in comparison to different masonries. This reduces
structural loading due to which economies expended on structural & foundation support is
saved.
4. Cavities on brick veneer wall can act as an insulating agent.
5. It looks fancy, needs little maintenance. It does not need painting either.
6. They are durable and fireproof.
How to install brick veneer
The steps of installing brick veneer in a wall are thoroughly explained below:
Step 1: Preparing wall for tile – First of all, make sure that the wall where brick veneer is to be
applied, is clean and smooth. Dust & debris makes it difficult for the glue to bond properly. Keep
level & ledger for placing the bricks.
Step 2: Cutting the bricks – After you finish cleaning, you can start cutting the bricks with the
help of diamond blade grinder or saw.
Step 3: Installing corner bricks – Start installing from the button corner of the wall by pressing
a full brick to the outer edge of the lower corner of the wall. Continue upward with a half cut thin
brick in a pattern of full-half-full-half alternately.
Step 4: Installing full rows – Same pattern has to be followed half-way up from the start. Now,
you can go back down to the bottom of the wall and start running the full bricks to finish the first
row, or “course.”
Step 5: Checking the rows are level – Every time, you have to make sure that rows are placed
on a straight level.
Step 6: Leaving space for Grouting – You have to leave grout joints between upper & lower
rows or between the adjacent bricks. The width of grout joints can be 3/8” to 1/2”.
Step 7: Installing remaining bricks – After completing half-way, the brick can be placed till
ceiling following same method as explained above.
Step 8: Grouting – After you have finished placing the bricks, allow the bricks to dry for at least
24 hours. Then you can fill the grout joints using the Portland cement.
Types of Bricks

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There are different types of bricks available on the market used for various kinds of purposes.
These bricks can be categorized under various headings and subheadings on different basis. The
various classifications of types of bricks are briefly discussed below.
Classification based on method of manufacturing
Bricks can broadly be categorized into two types as follows on the basis of how its manufactured:
1. Unburnt or sun-dried bricks
2. Burnt bricks
Unburnt bricks
Unburnt bricks or sun-dried bricks are the types which are dried with the help of heat received
from sun after the process of moulding. These bricks can only be used in the construction of
temporary and cheap structures. Such bricks should not be used at places exposed to heavy rains.
Burnt Bricks
Burnt bricks are prepared by burning the brick-mould in the kiln inside the factory. These are the
most commonly used bricks for construction works. They can be further classified into following
four categories:
First class bricks
These bricks are table-moulded and of standard shape and they are burnt in kilns. The surfaces and
edges of the bricks are sharp, square, smooth and straight. They comply with all the qualities of
good bricks. These bricks are used for superior work of permanent nature.

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Second class brick
These bricks are ground-moulded and they are burnt in kilns. The surface of these bricks is
somewhat rough and shape is also slightly irregular. These bricks may have hair cracks and their
edges may not be sharp and uniform. These bricks are commonly used at places where brickwork
is to be provided with a coat of plaster.
Third class bricks
These bricks are ground-moulded and they are moulded in kilns. These bricks are not hard and
they have rough surfaces with irregular and distorted edges. These bricks give dull sound when
struck together. They are used for unimportant and temporary structures and at places where
rainfall is not heavy.
Fourth class bricks
These are over-burnt type of brick with irregular shape and dark colour. These bricks are used as
aggregate for concrete in foundations, floors, roads, etc. because of the fact that the over-burnt
bricks have a compact structure and hence they are sometimes found to be stronger than even the
first class bricks.
Classification based on shape
The ordinary bricks are rectangular solids. But sometimes the bricks are given different shapes to
make them suitable for particular type of construction. Here we have enlisted different types of
bricks available with various shapes:
1. Bullnose brick: A brick moulded with a rounded angle is termed as a bullnose. This type
of brick is used for a rounded quoin. A connection which is formed when a wall takes a
turn is known as quoin. The centre of the curved position is situated on the long centre-line
of brick.
2. Channel bricks: These types of bricks are moulded to the shape of a gutter or a channel
and they are often glazed. These bricks are used to function as drains.
3. Coping bricks: These bricks are made to suit the thickness of walls on which coping is to
be provided. Such bricks take various forms such as chamfered, half round or saddle-back.
4. Cownose bricks: A brick moulded with a double bullnose on end is known as a cownose.
5. Curved sector bricks: These bricks are in the form of curved sector and they are used in
the construction of circular brick masonry pillar, brick chimneys, etc.
6. Hollow bricks: These are also known as the cellular or cavity bricks. Such bricks have
wall thickness of about 20mm to 25mm. They are prepared from special homogeneous
clay. They are light in weight about one-third the weight of the ordinary brick of the same
size. These types of bricks can be laid almost about four times as fast as the ordinary bricks
and thus the use of such bricks leads to speedy construction. They also reduce the
transmission of heat, sound and damp. They are used in the construction of partitioning.
7. Paving bricks: These bricks are prepared from clay containing a higher percentage of iron.
The excess iron vitrifies the bricks at a low temperature. Such bricks resist better the

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abrasive action of traffic. The paving bricks may be plain or chequered. These bricks are
extensively used for garden walks, street pavements, stable floors, etc. These types of
bricks also render the floor less slippery.
8. Perforated bricks: These bricks contain cylindrical holes throughout their thickness.
These bricks are light in weight and they require less quantity of clay for their preparation.
The drying and burning of these bricks are also easy. If perforated bricks of large size are
used, it will result in the increase of output of mason. The perorated bricks are used in the
construction of panels for lightweight structures and multi-storeyed framed structures.
They may be circular, square rectangular or any other regular shape in cross-section. The
distance between the side of brick and edge of perforation should not be less than 15mm.
The distance between the edges of successive perforations should preferably be not less
than 10mm. The water absorption after immersion for 24 hours in water should not exceed
15 percent by weight. The compressive strength of perforated bricks should not be less than
7 N/mm2
on gross area.
9. Purpose-made bricks: In order to achieve certain purpose, these types of bricks are made.
The splay or cant bricks are made for jambs of doors and windows. The arch bricks are
made of wedge shape to keep mortar joint of uniform thickness. The ornamental bricks are
prepared for corbels, cornices, etc. Similarly, engineering bricks are prepared for
constructions where high durability, compression strength and adequate resistance to
sudden shocks are required. These types of bricks are usually more costly than the ordinary
bricks. But they grant safe, clean and quick construction. Hence, their cost is justified by
their excellent performance in situation for which they are purposely prepared.
Cement
A cement is a binder, a substance that sets and hardens and can bind other materials together. It is
a powdery substance made by calcining lime and clay, mixed with water to form mortar or mixed
with sand, gravel, and water to make concrete. The natural cement is obtained by burning and
crushing the stones containing clay, carbonate of lime, and some amount of carbonate of magnesia.
The clay content in such stones is about 20 to 40 percent. The natural cement is brown in color
and its best variety is known as the Roman Cement. It closely resembles very closely eminent

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hydraulic lime. It sets very quickly after addition of water. It is not so strong as artificial cement.
Artificial cement is obtained by burning, at a very high temperature, a mixture of calcareous and
argillaceous materials. The mixture of ingredients should be intimate and they should be in correct
proportion. The calcined product is known as the clinker. A small quantity of gypsum is added to
the clinker and it is then pulverized into very fine powder which is known as the cement.
The common variety of artificial cement is known as the normal setting cement or ordinary cement.
The various varieties of artificial cement exceeding 30 in number are available in the market at
present. Normal setting or ordinary or Portland cement has a production of about two-third of the
total production of cement.
Contents:
 Difference
 Composition
 Properties
Differences between Cement and Lime
The differences between ordinary cement & lime are as follows:
1. The cement can be used under conditions and circumstances which are not favourable for
lime.
2. The cement, when converted into a paste form, sets quickly.
3. The colors of cement and lime are different.
4. When water is added to the cement, no heat is produced and there is no slaking action.
Composition of ordinary cement
The ordinary cement contains two basic ingredients, namely, argillaceous and calcareous. In
argillaceous materials, the clay predominates and in calcareous materials, the calcium carbonate
predominates. A typical chemical analysis of a good ordinary cement along with the desired range
is as follows:
 Lime: 62-67 %
 Silica: 17-25 %
 Alumina: 3-8 %
 Calcium sulphate: 3-4 %
 Iron oxide: 3-4 %
 Magnesia: 0.1-3 %
 Sulphur: 1-3 %
Properties of Cement

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Following are the important properties of a good cement which primarily depend upon its chemical
composition, thoroughness of burning and fineness of grinding:
1. It gives strength to the masonry.
2. It is an excellent binding material.
3. It is easily workable.
4. It offers good resistance to the moisture.
5. It possesses a good plasticity.
6. It stiffens or hardens early.
Rapid Hardening Cement
Rapid Hardening Cement (RHC) are also called high early strength cement. The prime difference
between the rapid hardening cement and ordinary Portland cement is the lime content. Large
proportion of lime is the distinguishing feature of rapid hardening cement.
Manufacturing
Rapid hardening cement is burnt at a higher temperature than that of the OPC under more
controlled conditions.
Strength
The 3 days strength of rapid hardening cement is equivalent to the 7 days strength of OPC when
the water-cement ratio for both the cement is taken to be same. The increased rate of strength is
due to the fact that higher proportion of tri-calcium silicate (C3S) is contained in RHC along with

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finer grinding of the cement clinker. Though, the rate at which RHC gains strength is higher than
the rate at which OPC gains strength, the ultimate strength is only a bit higher for RHC.
Properties
 Initial Setting Time: 30 minutes
 Final Setting Time: 600 minutes
 The specific surface is greater than 3250 cm2
/gm.
 RHC is lighter than OPC.
 The curing period for RHC is less.
Uses
Rapid hardening cement is mostly used in construction of road where the traffic cannot be halted
for long period of time. Besides, RHC is used where the formwork need to be removed early for
reuse. It is also used on those circumstances where sufficient strength for further construction is
wanted as quickly as practicable. These are also used in manufacturing precast slabs, posts,
electric poles.
Advantages
 As the curing period for rapid hardening cement is less, it turns out to be economical.
 Shrinkage during curing and hardening of cement is less in case of RHC.
 RHC are good at Sulphur resistance.
 Good speed of construction can be achieved as the strength is gained in relatively shorter
time.
Disadvantages
 It is expensive than Ordinary Portland Cement.
Extra Rapid Hardening Cement
Manufacturing: Intergrinding Calcium Chloride (CaCl2) with RHC, Extra RHC can be
obtained. The percentage of Calcium Chloride during the manufacturing process should not
exceed 3%.
Strength: Strength of Extra RHC is about 25 % higher than that of the RHC at 1-2 days whereas
the strength exceeds by only 10-20 % after 7 days.
Uses: Extra rapid hardening cement is used for cold weather concreting.
Types of Cement

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In addition to ordinary cement, following are the other important types of cement:
1. Acid resistant cement
2. Blast furnace cement
3. Coloured cement
4. Expanding cement
5. High Alumina cement
6. Hydrophobic cement
7. Low heat cement
8. Pozzolana cement
9. Quick setting cement
10. Rapid hardening cement
11. Sulphate resisting cement
12. White cement.
13. Air entraining cement
Above types of cement are discussed briefly here:
Acid-resistant cement
Acid-resistant cement is composed of the following:
1. Acid-resistance aggregates such as quartz, quartzites, etc.
2. Additive such as sodium fluosilicate Na2SiF6
3. Aqueous solution of sodium silicate or soluble glass.
The addition of additive sodium flousilicate accelerates the hardening process of soluble
glass and it also increases the resistance of cement to acid and water.

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The binding material of acid-resitance cement is soluble glass which is a water solution
of sodium silicate, Na2O.nSiO2 or potassium silicate, K2O.nSiO2, where n is the glass
modulus.
The acid-resistance cement is used for acid-resistance and heat resistance coatings of
installations of chemical industry. It is not water-resistant and it fails when attacked by
water or weak acids. By adding 0.5 percent of linseed oil or 2 percent of ceresit, its
resistance to the water is increased and it is then known as the acid and water resistant
cement.
Blast furnace cement
For this cement type, the slag as obtained from blast furnace is used. The slag is a waste
product in the manufacturing process of pig-iron and it contains the basic elements of
cement, namely alumina, lime and silica. The clinkers of cement are ground with about
60 to 65 percent of slag.
The properties of this cement are more or less the same as those of ordinary cement. Its
strength in early days is less and hence it requires longer curing period. It proves to be
economical as slag, which is a waste product, is used in its manufacture. This cement is
durable, but not suitable for use in dry arid zones.
Coloured cement
The cement of desired colour may be obtained by intimately mixing mineral pigments with
ordinary cement. The amount of colouring material may vary from 5 to 10 percent. If this
percentage exceeds 10 percent, the strength of cement is affected.
The chromium oxide gives green colour. The cobalt imparts blue colour. The iron oxide
in different proportions gives brown, red or yellow colour. The manganese dioxide is used
to produce black or brown coloured cement.
These types of coloured cement are widely used for finishing of floors, external surfaces,
artificial marble, window sill slabs, textured panel faces, stair treads, etc.
Expanding cement
This type of cement is produced by adding an expanding medium like sulpho-aluminate
and a stabilising agent to the ordinary cement. Hence this cement expands whereas other
cements shrink.
The expanding cement is used for construction of water retaining structures and also for
repairing the damaged concrete surfaces.
High Alumina cement

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This cement is produced by grinding clinkers formed by calcining bauxite and lime. It is
specified that total alumina content should not be less than 32 percent and the ratio by
weight of alumina to lime should be between 0.85 to 1.30.
Hydrophobic cement
This type of cement contains admixtures which decreases the wetting ability of cement
grains. The usual hydrophobic admixtures are acidol, napthenesoap, oxidized petrolatum,
etc. Use of hydrophobic cement considerably increases the water resistance of an
concrete.
Low heat cement
The considerable heat is produced during the setting of cement. In order to reduce the
amount of heat, this type of cement is used. It contains lower percentage of tricalcium
aluminate C3A of about 5% and higher percentage of dicalcium silicate C2S of about 46%.
This cement possesses less compressive strength. The initial setting time is about one
hour and final setting time is about 10 hours. It is mainly used for mass concrete work.
Pozzolana cement
Pozzolana is a volcanic powder. It is found in Italy near Vesuvius. This type of cement is
used to prepare mass concrete of lean mix and for marine structures. It is also used in
sewage works ad for laying concrete under water.
Quick setting cement
This cement is produced by adding a small percentage of aluminium sulphate and by
finely grinding the cement. The percentage of gypsum or retarder for setting action is also
greatly reduced. The addition of aluminium sulphate and fineness of grinding are
responsible for accelerating the setting action of cement. The setting action of cement
starts within five minutes after addition of water and it becomes hard like stone in less
than 30 minutes or so.
The extreme care is to be taken when this cement is used as mixing and placing of
concrete are to be completed in a very short period. This type of cement is used to lay
concrete under static water or running water.
Rapid hardening cement
The initial and final setting times of this cement are same as those of ordinary cement.
But it attains high strength in early days. It contains high percentage of tricalcium silicate
C3S to the extent of about 56%.
Sulphate resisting cement

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In this cement, the percentage of tricalcium aluminate C3A is kept below 5 percent and it
results in the increase in resisting power against sulphates.
This type of cement is used for structures which are likely to be damaged by severe
alkaline conditions such as canal linings, culverts, siphons, etc.
White cement
This just a variety of ordinary cement and is prepared from such raw materials which are
practically free from colouring oxides of iron, manganese or chromium. For burning of this
cement, the oil fuel is used instead of coal. It is white in colour and is used for floor finish,
plaster work, ornament work, etc.
Air entraining cement
It is produced by adding indigenous air entraining agents such as resins, glues, sodium
salts of Sulphates etc during the grinding of clinker. This type of cement is specially suited
to improve the workability with smaller water cement ratio and to improve frost resistance
of concrete.
Uses of cement

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At present, the cement is widely used across the world in the construction of various engineering
structures. It has proved to be one of the leading engineering material of modern times and has no
rivals in production and applications. Cements may be used alone (i.e., “neat,” as grouting
materials), but the normal use is in mortar and concrete in which the cement is mixed with inert
material known as aggregate to form a strong binding material. Following are various possible
applications or uses of cement:
1. The most significant use of cement is production of concrete and mortar.
2. Cement mortar can be used for masonry work, plaster, pointing, etc.
3. Cement concrete can be used for laying floors, roofs, constructing lintels, beams, weather
sheds, stairs, pillars, etc.
4. It can be used for construction of important engineering structures such as bridges, culvert,
dams, tunnels, storage reservoirs, light houses, docks, etc.
5. It can also be used for construction of water tanks, tennis courts, septic tanks, lamp posts,
roads, telephone cabins, etc.
6. It can be used for making joints for drains, pipes, etc.
7. It can be used for manufacturing precast pipes, garden seats, artistically designed urns,
flower pots, dust bins, fencing posts, etc.
8. It can be used for preparation of foundations, watertight floors, footpaths, etc.
9. It can be used for creating fire-proof structures in the form of concrete. Also, it can be used
for making acid-resistance and waterproof structures.
10. Colored cement can be used for decorating or coloring the structures.
11. It can be used for shotcreting the tunnel or geological walls to strength the structure.
Despite so many uses of cements, it has few demerits. However, its usability far overcomes its
demerits. Some of the negatives of cement are as follows:
1. Structure once build out of cement are difficult to be displaced or reused. They can’t be
easily recycled like plastics or steels.
2. Cement structure are very heavy. So, while building skyscrapers, it can’t be totally build
on cement. Instead steel structures are placed.
High Alumina Cement

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High Alumina Cement is an inorganic material that form a dense texture when it reacts with
water and has a excellent refractory, quick hardening property and resistance to chemical attacks.
This type of cement is produced by grinding clinkers formed by calcining bauxite and lime. The
bauxite is an aluminium ore. It is specified that total alumina content should not be less than 32
percent and the ratio by weight of alumina to the lime should be between 0.85 and 1.30. This
cement is known by the trade names of Cement Fondu in England and Lumnite in America.
Characteristics of High Alumina Cement
The characteristics of this cement can be surfacely summarized in following points:
 High alumina cement has low pH
 It has high refractoriness
 It has high durability in sulfuric acid
 It hardens rapidly
 It is less reactant than alumina or hydraulic lime
 It acts as a bonding material when added in refractory castables because it forms ceramic
bond at high temperatures
 It has high resistance to chemical corrosion. So, it is widely used also in construction of
water pipes, sewage pipes, factory drains, coastal constructions and in factory chimneys.
Advantages of High Alumina Cement

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Following are the advantages of High Alumina Cement:
1. The initial setting time of this cement is more than 3.5 hours. The final setting setting
time is about 5 hours. It therefore allows more time for mixing and placing operations.
2. It can stand high temperature.
3. It evolves great heat during setting. It is therefore not affected by frost.
4. It resists the action of acids in a better way.
5. It sets quickly and attains higher ultimate strength in a short period. Its strength after 1
day is about 40 N/mm2
and that after 3 days is about 50 N/mm2
.
6. Its setting action mainly depends on the chemical reactions and hence it is not necessary
to grind it to fine powder.
Disadvantages of High Alumina Cement
Following are the disadvantages of High Alumina cement:
1. The extreme care is to be taken to see that it doesn’t come in contact with even traces of
lime or ordinary cement.
2. It cannot be used in mass construction as it evolves great heat as it sets soon.
3. It is costly
Hydrophobic cement

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Hydrophobic cement contains admixtures which decreases the wetting ability of cement grains.
The usual hydrophobic admixtures are acidol, naphthenesoap, oxidized petrolatum, etc. These
substances form a thin film around cement grains. Hydrophobic cement is obtained by grinding
portland cement clinker with a film-forming substance such as oleic acid in order to reduce the
rate of deterioration when the cement is stored under unfavourable conditions.
When water is added to hydrophobic cement, the absorption films are torn off the surface and they
do not in any way, prevent the normal hardening of cement. However, in initial stage, the gain in
strength is leas as hydrophobic films on certain grains prevent the interaction with water. However,
its strength after 28 days is equal to that of ordinary Portland cement.
When hydrophobic cement is used, the fine pores in concrete are uniformly distributed and thus
the frost resistance and the water resistance of such concrete are considerably increased.
Oxygen diffusion coefficient of Hydrophobic cement
The oxygen diffusion coefficient through hydrophobic cement-based materials fully immersed in
water are determined by potentiostatic measurements on concrete and by the use of a diffusion cell
on cement pastes and mortars. The obtained results show that very high oxygen diffusion occurs
through cement paste, mortar and concrete made with hydrophobic admixture as opposed to
negligible diffusion through the reference cement matrix without admixture. Moreover, the oxygen
diffusion coefficients measured through hydrophobic cement matrices immersed in water are
comparable with those reported in literature for unsaturated cement materials in air. These
experimental results appear to confirm that oxygen dissolved in water directly diffuses as a gaseous
phase through the empty pores of a hydrophobic cement matrix. This could explain the severe
corrosion of steel reinforcement embedded in cracked hydrophobic concrete immersed in an
aqueous chloride solution observed in various work.
Advantages & Disadvantages of Hydrophobic cement
The advantages of Hydrophobic cement are as follows:
 This cement can be used in the construction of water structures such as dams, spillways, or
other submerged structures.
 The strength of this cement is same as that of ordinary portland cement after 28 days.
 It can be used in cold weather conditions as well.
The disadvantages of Hydrophobic cement are as follows:
 Cost is high as it is very expensive.
 Application is labor intensive.
Cement Ingredients

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The ordinary cement contains two basic ingredients, namely, argillaceous and calcareous. In
argillaceous materials, the clay predominates and in calcereous materials, the calcium carbonate
predominates. A typical chemical analysis of a good ordinary cement along with the desired range
is as follows:
Ingredient Composition (Percent) Range (Percent)
Lime (CaO) 62 62 to 67
Silica (SiO2) 22 17 to 25
Alumina (Al2O3) 5 3 to 8
Calcium Sulphate (CaSO4) 4 3 to 4
Iron oxide (Fe2O3) 3 3 to 4
Magnesia (MgO) 2 0.1 to 3
Sulphur (S) 1 1 to 3
Alkalies 1 0.2 to 1
Functions of cement ingredients
The ingredients of ordinary cement, as mentioned above, perform the following functions:
Lime (CaO): This is the important ingredient of cement and its proportion is to be carefully
maintained. The lime in excess makes the cement unsound and causes the cement to expand and
disintegrate. On the other hand, if lime is in deficiency, the strength of cement is decreased and it
causes cement to set quickly.
Silica (SiO2): This is also an important ingredient of cement and it gives or imparts strength to the
cement due to the formation of dicalcium and tricalcium silicates. If silica is present in excess
quantity, the strength of cement increases but at the same time, its setting time is prolonged.

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Alumina (Al2O3): This ingredient imparts quick setting property to the cement. It acts as a flux
and it lowers the clinkering temperature. However, the high temperature is essential for the
formation of a suitable type of cement and hence the alumina should not be present in excess
amount as it weakens the cement.
Calcium Sulphate (CaSO4): This ingredient is in the form of gypsum and its function is to
increase the initial setting time of cement.
Iron oxide (Fe2O3): This ingredient imparts color, hardness and strength to the cement.
Magnesia (MgO): This ingredient, if present in small amount imparts hardness and color to the
cement. A high content of magnesia makes the cement unsound.
Sulphur (S): A very small amount of sulphur is useful in making sound cement. If it is in excess,
it causes cement to become unsound.
Alkalies: The most of the alkalies present in raw materials are carried away by the flue gases
during heating and the cement contains only a small amount of alkalies. If they are in excess, the
cause a number of troubles such as alkali-aggregate reaction, efflorescence and staining when used
in concrete, brickwork or masonry mortar.
Cement Industry
The manufacturing of Portland cement was started in England around 1825. Belgium and Germany
started the cement industries in 1855. America started the same in 1872 while India started in 1904.
The first cement factory in India was installed in Tamil Nadu in 1904 by South India Industry
Limited and then onwards a number of factories manufacturing cement were started. India is the
second largest producer of cement in the world after China. India is followed by Indonesia, Iran,
United States, Brazil, Turkey, Russia, Vietnam & Japan.

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The main machinery in a cement plant comprises limestone crusher and stacker reclaimer, roller
mills for grinding, coal crushers, packers, pollution control equipment, belt conveyers, etc.
It is a fact that the cement industry is a major consumer of the energy using 1.5 percent of the
world-fuel and about 2 percent of electricity produced globally. Hence, the attention is paid to find
out ways and means to optimize power consumption in raw materials, coal and clinker grinding.
One of such development is the vertical roller mills (VRM) which allows for higher drying
capacity with less consumption of power. The coal is also increasingly replaced by the groundnut
husk to fire the kiln.
The technology for mining in the cement industry has also been improved. Instead of conventional
mining, the process known as the surface mining is adopted. It is carried out without drilling,
blasting, and crushing when extracting valuable minerals. The surface mining greatly reduces the
vibrations, noise and dust loads.
It is encouraging to note that a few cement companies have changed their philosophy from selling
to marketing. The philosophy of marketing always keeps focus on the customer requirements.
Some of the leading cement companies have introduced innovative methods of marketing. For
instance, the companies have opened chain of office units from where free technical services are
given to the customers through qualified and experienced application civil engineers. The
companies also use various medias like television, radio, press, technical magazines, lecture series,
seminars, etc. to educate the masses. Such a trend has brought consumer awareness to use right
cement for right end application.
World’s top cement companies
Top global cement companies ranked on the basis of capacity (as until 2013) are as follows:
Rank Company/Group Country Capacity (Mt/yr) No. of plants
1 Lafarge France 224 161
2 CNBM China 221 –
3 Holcim Switzerland 218 147
4 Anhui Conch China 209 –
5 Jidong Development China 130 43
6 HeidelbergCement Germany 122 103
7 Sinoma China 100 –
8 Cemex Mexico 95 57
9 Shanshui China 93 –
10 China Resources China 74 17
11 Taiwan Cement Corp Taiwan 71 –
12 Italcementi Italy 68 53
13 Votorantim Brazil 57 22
14 UltraTech India 51 22
15 Buzzi Italy 45 39
16 Tianrui China 43 42
17 Eurocement Russia 40 16

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18 Cimpor Portugal 38 39
19 Intercement Brazil 38 39
20 Jaypee India 33 12
Cement Manufacturing Process
The entire manufacturing process in a modern plant is now controlled through a microprocessor
based programmable logic control system to maintain uniform quality of cement and a high rate
of production. The entire operation of the plant is controlled centrally in a single control room and
the plant employs minimum of manpower.
The modern plants have also taken adequate care to prevent the environmental pollution and dust
nuisance to its surrounding areas. The cement mills have electro-static precipitators (ESP) installed
to check the dust emissions. The bag filters and glass bag houses are located at various locations
to prevent dust emission and to ensure healthy and hazard-free atmosphere.
Following three distinct operations are involved in the manufacturing of normal setting or ordinary
or Portland cement:
 Mixing of raw materials
Dry Process
 Burning
 Grinding
Mixing of raw materials
The raw materials such as limestone or chalk and shale or clay may be mixed either in dry condition
or in wet condition. The process is accordingly known as the dry process or the wet process of
mixing.

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Dry process (modern technology)
In this process, the raw materials are first reduced in size of about 25mm in crushers. A current of
dry air is then passed over these dried materials. These materials are then pulverized into fine
powder in ball mills and tube mills. All these operations are done separately for each raw material
and they are stored in hoppers. They are then mixed in correct proportions and made ready for the
feed of rotary kiln. This finely ground powder of raw materials is known as the raw mix and it is
stored in storage tank.
The dry process has been modernized and is widely used at present because of following
reasons:
 Competition: At present, several dry process cement plants are vying with each other. The
cement consumers in general and the practicing civil engineers in particular are greatly
benefited by such competition.
 Power: The blending of dry powders has now perfected and the wet process, which required
much higher power consumption can be replaced with confidence.
 Quality of cement: It is found that the quality of the production no longer depended on the
skilled operators and workmen because temperature control and proportioning can be done
automatically through a centralized control room.
 Technology: There has been several advances in instrumentation, computerization and
quality control.
Following is the procedure of manufacturing cement by dry process using modern
technology:
1. Boulders of limestone upto 1.2m size are transported in huge dumpers upto 300kN capacity
and dumped into the hopper of the crusher.
2. The hammer mill crushers of single stage are now used for crushing. The crushed limestone
now of 75mm size is moved from crusher by a series of conveyors for stacking. The stacker
helps in spreading the crushed materials in horizontal layers and the reclaimer restricts the
variation of calcium carbonate in crushed limestone to less than 1% thereby minimizing
quality variation in the materials.
3. The argillaceous or clay materials found in the quarry are also dumped into the crusher and
stacked along with the limestone.
4. The crushed materials are checked for calcium carbonate, lime, alumina, ferrous oxide and
silica contents. Any component found short is added separately.
5. The additive material and crushed limestone are conveyed to the storage hoppers. The raw
materials are fed to the raw mill by means of a conveyor and proportioned by use of weigh
feeders which are adjusted as per the chemical analysis done on the raw materials taken
from the hoppers time to time.
6. The materials are ground to the desired fineness in the raw mill. The fine powder which
emerges as a result of the grinding in the raw mill is blown upwards, collected in cyclones
and fed to the giant sized continuous blending and storage silo by use of aeropole.
7. The material is dropped merely by gravity from the blending to the storage silo thereby
conserving power.

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8. The material is then once again pumped using an aeropole into the preheater with
temperature increased from 60°C to 850°C by blowing hot gas at temperature of 1000°C.
9. The maerial from the bottom of the preheater is fed to the rotary kiln.
Burning
In modern technology of dry process, the coal brought from the coal fields is pulverized in vertical
coal mill and it is stored in silo. It is pumped with required quantity of air through the burners. The
preheated raw materials roll down the kiln and get heated in such an extent that the carbon dioxide
is driven off with combustion gases. The material is then heated to temperature of nearly 1400°C to
1500°C when it gets fused together. The fused product is known as the clinkers or raw cement.
The size of clinkers varies from 3mm to 20mm and they are very hot when they come out of
burning zone of kiln. The clinker temperature at the outlet of kiln is nearly 1000°C. A rotary kiln
of small size is provided to cool down the hot clinkers. It is laid in opposite direction and the cooled
clinkers having temperature at about 95°C are collected in containers of suitable sizes.
Grinding
The clinkers as obtained from the rotary kiln are finely ground in ball mills and tube mills. During
grinding, a small quantity, about 3 to 4 percent, of gypsum is added.
The gypsum controls the initial setting time of cement. If gypsum is not added, the cement would
set as soon as water is added. The gypsum acts as a retarder and it delays the setting action of
cement. It thus permits cement to be mixed with the aggregates and to be placed in position.
The grinding if clinkers in modern plants is carried out in the cement mill which contains
chromium steel balls of various sizes. These balls roll within the mill and grind the mixture which
is collected in a hopper and taken in the bucket elevator for storage in silos.
The cement from silos is fed to the packer machines. Most of the modern plants have electric
packing plant having provision to account for the weights of empty bags of different types and to
ensure a 50kg net weight of cement bag within ± 200g limit. Each bag of cement contains 50kg or
500N or about 0.035m3
of cement. These bags are automatically discharged from the packer to the
conveyor belts to different loading area. They are carefully stored in a dry place.
Air Entrained Concrete

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The process which involves the introduction of tiny air bubbles into concrete is called air
entrainment. And the concrete formed through this process is called air entrained concrete. Using
air entraining Portland cement or air entraining agents such as admixture, air entrainment is done
in concrete. The amount of air in such concrete is usually between four to seven percent of the
volume of concrete. It is measured by galvanometric method, volumetric method and pressure
method. The air bubbles relieve internal pressure on the concrete by providing chambers for
water to expand when it freezes.
Process
Here are the ways of incorporating air in concrete:
 Using gas forming materials as aluminium powder, zinc powder and hydrogen peroxide.
 Using surface active agents that reduces surface tension. They may be natural wood
resins and their soaps, animal or vegetable fats or oils, alkali salts of sulfonated or
sulphated organic compounds.
 Using cement dispersing agents.
Advantages
Some of the advantages of air entrained concrete are given below:
 Workability of concrete increases.
 Use of air entraining agent reduces the effect of freezing and thawing.
 Bleeding, segregation and laitance in concrete reduces.
 Entrained air improves the sulphate resisting capacity of concrete.
 Reduces the possibility of shrinkage and crack formation in the concrete surface.

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Disadvantages
Some of the disadvantages of air entrained concrete are given below:
 The strength of concrete decreases.
 The use of air entraining agent increases the porosity of concrete thereby reducing the
unit weight.
 Air-entrainment in concrete must not be done if the site control is not good. This is due to
the fact that the air entrained in a concrete varies with the change in sand grading, errors
in proportioning and workability of the mix and temperatures.
Concrete mix ratio
We all know that on mixing cement with sand, stone/aggregates and water, a paste will form
which can be used to bind the building materials together. This paste is also called as concrete.
The strength of this concrete mix is determined by the proportion on which these cement, sand,
stones or aggregates are mixed. There are various grades of concrete available in the market
based on these ratios. Some of them are: M10, M20, M30, M35, etc. So, what really does M10 or
M20 mean or represent.
“M” stands for “mix”. Mix represents concrete with designated proportions of cement, sand and
aggregate. And the number following “M” represents compressive strength of that concrete mix
in N/mm2
after 28 days. For example, for M20 grade of concrete mix, its compressive strength
after 28 days should be 20 N/mm2
.

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Concrete mix ratio table
Here is the standard chart table showing various grades of concrete mix design along with their
respective ratios of cement, sand and aggregates required.
Grades of Concrete Ratios of Concrete mix design
(Cement:Sand:Aggregate)
M5 1:5:10
M7.5 1:4:8
M10 1:3:6
M15 1:2:4
M20 1:1.5:3
M25 1:1:2
M30 1:0.75:1.5
M35 1:0.5:1
M40 1:0.25:0.5
As you can see in the table above, volume of sand is always kept half of that of aggregates in
these standard mix designs. You can measure and maintain these ratios by using buckets or some
other standard cubes which could be easily used throughout the project. It is necessary to
maintain consistency in each and every concrete mix prepared during the entire project. It is one
of the important job of site engineer/supervisor to inspect and enforce it.
Water content ratio in concrete mix
Besides water content also largely determine the strength & workability of concrete. Greater the
amount of water, higher will be the workability of concrete (more fluid) however it reduces the
strength of concrete. But if you keep water too low, workability of water will also reduce.
Therefore, it will be difficult to place such concrete in the structure. Amount of water required
may vary for same volume of concrete for various grades of concrete. Hence, a balance has to be
found in the construction site during concrete mixing.
Concrete Companies

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There are lot of concrete companies across the world located in various countries. We have tried
to list out some of the popular concrete companies from countries like France, India, Nepal, UK
& USA.
List of Concrete Companies in:
 France
 India
 Nepal
 UK
 USA
Concrete companies in France
Here is the list of top concrete companies manufacturing & supplying ready-mix and prefabricated
products in France.
Ready-mix concrete companies in France
These are the ready-mix companies in France:
1. Lafarge: The largest cement company in the world, Lafarge produces 7 different kind of
concrete products. From tailor-made to site-suitable concrete, Lafarge has every solution
for construction work.
2. Cemex: As a leading ready-mix concrete and aggregates producer, CEMEX is a key player
in the country’s national and regional development. It’s operations transport a significant

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quantity of materials by waterway, a more efficient and sustainable means of delivery than
trucks and trains.
Prefabricated concrete companies in France
Here is the list of prefabricated concrete companies in France:
1. OTEP
OTEP SA and AMSA France are both specialised in technologies and materials for the
pre stressed concrete industry. OTEP is widely recognised for its expertise and mastery of
technological products for pre stressed concrete. The company creates plants for products
made from pre stressed concrete: girders, preslabs, beams and structural elements, hollow
slabs, ornate columns, electric posts.
Saint-Gaudens – FRANCE
2. BAMBOO FRANCE
Supplier of Flooring, prefabricated concrete, Garden fittings, Bamboo and rattan items,
Shop fittings, bamboo
Belleville – FRANCE
3. MAISON BLEUE
This company is supplier of Concrete constructions, prefabricated concrete components,
prefabricated industrial and agricultural structures
La Rabateliere – FRANCE
4. PYRENEES PREFA
This company is supplier of Concrete products and conglomerates, prefabricated concrete
industry, prefabricated concrete components, construction of reinforced-concrete
structures for public works, reinforced concrete
Artix – FRANCE
5. GRIS CLAIR
This company is supplier of Flooring, prefabricated concrete, Concrete products and
conglomerates, Concrete blocks, Slabs – concrete, Floor-building units – hollow concrete
Mathay – FRANCE
6. EST PREFA : SPÉCIALISTE DU BÉTON PRÉFABRIQUÉ
This company is supplier of Structural work, Concrete constructions, prefabricated
reinforced concrete and concrete products and structures, construction of concrete
structures for public works
Atton – FRANCE
7. KNAUF ILE DE FRANCE
This company is supplier of Flooring, prefabricated concrete, Concrete products and
conglomerates
Marolles Sur Seine – FRANCE
8. STE GRANVIL’BETON
This company is supplier of Flooring, prefabricated concrete, Floor-building units –
hollow concrete, Concrete products and conglomerates, Poles, concrete, Concrete blocks
St Pair Sur Mer – FRANCE
9. BERSUB SARL
This company is supplier of Flooring, prefabricated concrete, Hunting and fishing
equipment and special products, Water sports – equipment, Air sports – equipment,

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Camping equipment
Saint-Genix-Sur-Guiers – FRANCE
10. STE ALPINE DE PREFABRICATION BETON
This company is supplier of Flooring, prefabricated concrete, Frameworks, concrete,
Slabs – concrete
La Batie Neuve – FRANCE
11. RECTOR LESAGE
This company is supplier of Flooring, prefabricated concrete, Concrete products and
conglomerates
Mulhouse – FRANCE
12. STE NAULLET
This company is supplier of Flooring, prefabricated concrete, Concrete products and
conglomerates, Concrete blocks, Pugging, hollow concrete slabs, Sewer pipes, concrete
La Roche Sur Yon – FRANCE
13. STAVEMARNE
This company is supplier of Flooring, prefabricated concrete, Concrete products and
conglomerates, Poles, concrete, Concrete blocks
Chaumont – FRANCE
14. ETS RUAUD SA
This company is supplier of Flooring, prefabricated concrete, Concrete products and
conglomerates
Elven – FRANCE
15. ETS CHATAIGNERE
This company is supplier of Flooring, prefabricated concrete, Tiles, Concrete products
and conglomerates
Fougeres – FRANCE
16. LUXE POOLS
This company is supplier of Swimming pools – equipment and installations for water
treatment, Swimming pools, installations and equipment, overflow swimming pool
Viriat – FRANCE
Concrete companies in India
Here is the list of top concrete companies & suppliers in India:
1. RDC Concrete (India) Pvt. Ltd.
2. Neptune Ready Mix Concrete (Part of RDC concrete)
3. Lafarge
4. UltraTech
5. CI Concrete India
6. ACC Limited
7. Ramco Ready Mix Concrete
8. PCM Cement Concrete Pvt. Ltd.
9. RMC Ready Mix (India)
10. Ironite Company of India Ltd.

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Concrete Companies in Nepal
Panchakanya Premix Pvt. Ltd. (Part of Panchakanya group of companies) is so far the only
concrete company in Nepal which provides ready-mix concrete to the clients. The company
undertakes supply orders for the construction industry in Kathmandu and nearby areas. The ready
mix concrete plant has been set up with a view to providing quality concrete and concrete products
like precast to the Nepalese market. Both material and equipment used are processed under optimal
technology to maintain consistency in quality. The production capacity per day is 200 cubic metre
(8-hour operation), whereas the production capacity is 4,32,000 cubic metre per annum (24-hour
operation). Due to concrete premix, construction process has become easier specially for large
projects. It not only cuts down on the construction time but also prevents mistakes in preparing the
mixture with right proportion of ingredients. The concrete range used are M15, M20, M25
and other grades as per the requirement. The target market of the company is Kathmandu
metropolitan city and its surrounding areas.
Concrete Companies in UK
Here is list of concrete companies maunfaturing & supplying ready-mix concrete & mortar in
various locations of UK:
1. MASONS MINIMIX
Horsham
2. MAYHEW EASYSCREED
Salisbury
3. TARMAC TOPMIX LTD
Nottingham
4. TARMAC TOPMIX LTD
Cardiff
5. TARMAC TOPMIX LTD
Telford
6. TARMAC NORTHERN LTD
Glasgow
7. TARMAC TOPMIX LTD
Derby
8. TARMAC TOPMIX LTD
Sheffield
9. TARMAC CENTRAL LTD
Accrington
10. TARMAC CENTRAL
Liverpool
11. TARMAC BUILDING PRODUCTS LTD
Cardiff
12. ACE MINIMIX
Retford
13. ACE MINIMIX
Newport

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14. ALBION SPECIALIST
Llangadog
15. CEMEX MATERIALS LTD
Runcorn
16. RICHMIX LTD
Chelmsford
17. JIM’LL MIX IT
London
18. FLOOR & WALL LTD
Scunthorpe
19. REMIX DRY MORTAR LTD
Fareham
20. SANDSFIELD READY MIX LTD
York
21. PREMIER MORTARS
Wolverhampton
22. READY MIX
Waltham Abbey
23. CEMEX MATERIALS LTD
Egham
24. CEMEX NI LTD
Ballymena
25. BATCHMIX LTD
Doncaster
26. ACE MINIMIX
Radstock
27. DUNGANNON MINI MIX CONCRETE
Dungannon
28. JABEZ CONCRETE
Camelford
Concrete Companies in USA
Here is the list of top concrete companies in USA:
1. Oldcastle Inc., Atlanta
2. Cemex Inc., Houston
3. Lafarge North America, Herndon, Va.
4. HeidelbergCement, Allentown, Pa.
5. Holcim Inc., Dundee, Mich.
6. Vulcan Materials Co., Birmingham, Ala.
7. Colas S.A., Roseland, N.J.
8. Martin Marietta Materials, Raleigh, N.C.
9. MDU Resources, Bismarck, N.D.
10. Buzzi Unicem, Bethlehem, Pa.
11. Taiheiyo Cement, Glendora, Calf.

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12. TXI, Dallas
13. Mitsubishi Materials Corp., Corona, Calif.
14. Titan America, Norfolk, Va.
15. S. Concrete Inc., Houston
16. Trinity Construction Products Group, Dallas
17. Grupo Cementos de Chihuahua, Chihuahua, Mex.
18. Italcementi Group, Nazareth, Pa.
19. Boral, Roswell, Ga.
20. Cementos Argos, Medellin, Colombia
Concrete blocks
The materials required for the production of the concrete blocks are aggregates, cement and water.
The aggregates of various types have been used with varying degree of success and they include
crushed stones, gravel, volcanic cinders, foamed slag, furnace clinker, etc. The aggregates are
selected by considering the weight, texture or composition of the unit designed. The strength,
texture and economy of the concrete block depend upon the careful grading of the aggregate. If
locally available aggregate is suitable, it will help in achieving the economy.
The cement used is ordinary Portland cement. The water required is the normal potable water.
Contents:
 Manufacturing
 Cellular
 Advantages
 Uses

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Manufacturing of concrete blocks
The fully automatic plants are available for the manufacturing of high strength concrete blocks.
These automatic machines produce superior quality concrete blocks. But they involve a large
capital investment. The manually operated machines are also available and they can be installed
at project site itself which further reduce the transportation cost of the concrete blocks from the
place of production to the place of actual use.
The processes involved in the manufacturing of the concrete blocks are as follows:
1. Selection and proportion of Ingredients: The main criteria for the selection of the
ingredients are the desired strength of the block. The greater the proportion of coarse
aggregate, the greater will be the strength of the quantity of cement used.
2. Mixing of ingredients: The blending of aggregates, cement and water should be done very
carefully. The mixing should preferably take place in a mechanical mixer. For hand mixing,
extreme care should be taken to see that the cement and aggregates are first mixed
thoroughly in dry state and the water is then added gradually.
3. Placing and vibration: The mixed concrete material is fed into the mould box upto the
top level and it is ensured that the box is evenly filled. The vibration of concrete is done
till it has uniformly settled in the mould box.
4. Curing: The block is watered after about one day of casting and it is continued for a
minimum of 7 days and preferably till 28 days. The longer the curing period, the better will
be the block.
Cellular concrete blocks
This is a lightweight building material produced by autoclaving a set mix of a fine siliceous
material such as fly-ash and binder in the form of lime. The cellular concrete blocks possess many
technical advantages such as better strength to weight ratio, better sound insulation, stability of
variations in temperatures and humidity, resistance to fire, low thermal conductivity, resistance to
water seepage, etc.
As these blocks are machine finished and uniform in size, the units require comparatively less
quantity of cement mortar and plaster can be completely avoided as the blocks are smooth and
uniformly coloured.
Advantages of concrete blocks
The use of concrete blocks as a masonry unit can be observed on many construction sites because
of the following advantages:
1. It increases the carpet area of the building because of small width of concrete block as
compared to the brick masonry wall.
2. It provides better thermal insulation, enhanced fire resistance and sound absorption.
3. It results in the saving of precious agricultural land which is used for manufacturing bricks.

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4. The blocks can be prepared in such a manner that the vertical joints can be staggered
automatically and thus the skilled supervision is reduced.
5. The construction of concrete block masonry is easier, faster and stronger than the brick
masonry.
6. The perfect shape and size of the concrete block makes the work of a mason much simpler.
7. There is saving in construction of mortar because the numbers of joints are reduced.
8. The utility can be further increased by producing reinforced concrete block (RCB) masonry
units. The blocks are provided two holes for placing suitable reinforcing bars and the
structure with RCB units could safely resist wind and earthquakes, if so designed. The
traditional beams and columns can be completely eliminated and the structure with RCB
units can be given a better appearance.
Uses of concrete blocks
In view of the advantages mentioned above, the concrete block masonry technique of construction
can be adopted on a large scale of mass housing and various civil engineering projects.
Mixing concrete
The process of rolling, folding and spreading of particles is known as the mixing of concrete.
The materials of concrete should be mixed thoroughly so that there is uniform distribution of
materials in the mass of concrete. The thorough mixing also ensures that cement water paste
completely covers the surfaces of aggregates. The mixing of materials of concrete can be done
either with hand or with the help of a cement mixer machine.
Hand Mixing

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For hand mixing, the materials are stacked on a water-tight platform, which may be either of wood,
brick or steel. The materials should be thoroughly mixed, at least three times, in dry condition
before water is added. The prepared mix should be consumed in 30 minutes after adding water.
The mixing by hand is allowed in case of small works of unimportant works where small quantity
of concrete is required. For important works, if hand mixing is to be adopted, it is advisable to use
10 percent more cement than specified.
Machine mixing
For machine mixing, all the materials of concrete, including water, are collected in a revolving
drum and then the drum is rotated for a certain period. The resulting mix is then taken out of the
drum. The features of machine mixing of concrete are as follows:
1. It is found that mixing of concrete materials with the help of machines is more efficient
and it produces concrete of better quality in a short time.
2. The mixers of various types and capacities are available in the market. They may either be
of tilting type or non-tilting type. They are generally provided with power-operated loading
hoppers. For small works, a mixer capable of producing concrete of one bag of cement is
used. For works such as roads, aerodromes, dams, etc. , special types of mixers are used.
3. The water should enter the mixer at the same time or before other materials are placed.
This ensures even distribution of water.
4. The concrete mixer should be thoroughly washed and cleaned after use. If this precaution
is not taken, the cakes of hardened concrete will be formed inside the mixer. These cakes
are not only difficult to remove at a later stage, but they considerably affect the efficiency
of the mixer.
5. The inside portion of the mixer should be inspected carefully at regular intervals. The
damaged or broken should be replaced.
6. The time of mixing concrete materials in the mixer and the speed of mixer are very
important factors in deciding the strength of concrete which is formed. The mixing time
should be rotated at a speed as recommended by the manufactures of the mixer.
7. The concrete discharged by the mixer, after thoroughly mixing concrete materials, should
be consumed within 30 minutes.
Curing of Concrete

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Curing is the process where the concrete surfaces are kept wet for a certain period after placing of
concrete so as to promote the hardening of cement. It consists of a control of temperature and of
the moisture movement from and into the concrete.
Contents:
 Purposes
 Period
 Effects
 Methods
Purposes of curing of concrete
Following are the objects or purposes of the curing of concrete:
1. Curing protects the concrete surfaces from sun and wind.
2. The presence of water is essential to cause the chemical action which accompanies the
setting of concrete. Normally, there is an adequate quantity of water at the time of mixing
to cause the hardening of concrete. But it is necessary to retain water until the concrete has
fully hardened.
3. The strength of concrete gradually increases with age, if curing is efficient. This increase
in strength is sudden and rapid in early stages and it continues slowly for an indefinite
period.
4. By proper curing, the durability and impermeability of concrete are increased and
shrinkage is reduced.
5. The resistance of concrete to abrasion is considerably increased by proper curing.
Period of curing

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This depends upon the type of cement and nature of work. For ordinary Portland cement, the curing
period is about 7 to 14 days. If rapid hardening cement is used, the curing period can be
considerably reduced.
Effects of improper curing
Following are the major disadvantages of improper curing of concrete:
1. The chances of ingress of chlorides and atmospheric chemicals are very high.
2. The compressive and flexural strengths are lowered.
3. The cracks are formed due to plastic shrinkage, drying shrinkage and thermal effects.
4. The durability decreases due to higher permeability.
5. The frost and weathering resistances are decreased.
6. The rate of carbonation increases.
7. The surfaces are coated with sand and dust and it leads to lower the abrasion resistance.
The above disadvantages are more prominent in those parts of structures which are either directly
exposed or those which have large surfaces compared to depth such as roads, canals, bridges,
cooling towers, chimneys, etc. It is therefore necessary to protect the large exposed surfaces even
before setting. Otherwise it may lead to a pattern of fine cracks.
Methods of curing
Following two factors are considered while selecting any mode of method of curing:
1. The temperature should be kept minimum for dissipation of heat of hydration.
2. The water loss should be prevented.
Thus all the methods of curing of concrete are derived from the basic principle of lowering of the
surface temperatures and prevention of water evaporation. Several specialized curing techniques
are employed in the modern construction work, but the most commonly employed methods of
curing are as follows:
1. Ponding with water.
2. Covering concrete with wet jute bags.
3. Covering concrete with water-proof paper of polythelene sheets and holding it in position.
4. Intermittent spraying with water and continuous sprinkling of water.
5. Applying curing compounds.
No-fines Concrete

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The no-fines concrete consists of cement, coarse aggregate and water. Thus the fine aggregate or
sand is eliminated and such concrete has been adopted for cast-in-situ external load bearing walls
of single and multi-storey houses, small retaining walls, damp-proofing sub-base material, etc.
Advantages of no-fines concrete
Following are the advantages of no-fines concrete:
1. As compared to the conventional concrete, the drying shrinkage of no-fines concrete is
relatively low.
2. As there is absence of capillary passages, there is no transmission of water by capillary
action.
3. It is a type of lightweight concrete and hence it grants the advantages associated with the
lightweight concrete construction.
4. It possesses better insulating characteristics than conventional concrete because of the
presence of large voids.
5. There is direct saving in material requirements as no-fines concrete doesn’t require sand
which results in considerable saving of cement per m3
of concrete.
6. The unit weight of no-fines concrete is about two-thirds of the unit weight of conventional
concrete. Hence the pressure on formwork is greatly reduced. Also, the formwork need not
be watertight and hence it is possible to use cheap formwork.
7. As no-fines concrete doesn’t segregate, it can be dropped from a considerable height and
placed in very high lifts.
Disadvantages of no-fines concrete
Following are the however the limitations of the no-fines concrete:
1. As no-fines concrete has little or no cohesion in the fresh state, it requires long time for the
removal of forms.

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2. It is highly permeable as compared to conventional concrete and hence the rendering of
walls becomes essential. However, in certain cases, such as drainage layers in soils, the
advantage of quality of high permeability of no-fines concrete can be taken.
The compressive, bond and flexural strength of no-fines concrete are considerably lower than those
of conventional concrete. The use of reinforcement in no-fines concrete is generally not
recommended. However, if reinforcement is to be used, it is to be coated with a thin layer of about
3mm thickness of cement paste so as to improve the bond characteristics and also to improve the
resistance to corrosion.
Ready Mix Concrete
Ready-mix concrete (RMC) is a type of concrete which is manufactured in a cement factory, or
specifically known as the batching plant, according to a given set of proportions, and then delivered
to a work site, by truck mounted with mixers. This results in a precise mixture, allowing specialty
concrete mixtures to be developed and implemented on construction sites. The fist factory which
produced ready mix concrete was built in 1930s; however, the industry didn’t begin to expand
until late 80s. Since then it has continued to grow significantly.
Ready mix concrete is sometimes preferred over on-site concrete mixing because of the volume it
can produce with precision of proportion of mixtures and also due to reduced work site confusion.
Using a pre-determined concrete mixture reduces flexibility, both in the supply chain and in the
actual components of the concrete.
Ready-mix concrete is also termed as the customized concrete products for commercial purpose.
Ready-mix concrete (RMC) refers to concrete that is specifically manufactured for delivery to the
customer’s construction site in a freshly mixed and plastic or unhardened state. Concrete itself is
a mixture of Portland cement, water and aggregates comprising sand and gravel or crushed stone.
In traditional work sites, each of these materials is procured separately and mixed in specified
proportions at site to make concrete. Ready-mix concrete is bought and sold by volume – usually
expressed in cubic meters (cubic yards in the US).

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Ready-mix concrete is manufactured under controlled operations and transported and placed at
site using sophisticated equipment and methods. In 2011, there were 72,924 workers working in
2,223 companies that produced Ready Mix Concrete in the United States.
Contents:
 Process
 Advantages
 Disadvantages
 Volumetric Mixer
Process of Ready-mix concrete
Ready mix concrete has cement, aggregates, sand, water and other chemicals, which are weigh-
batched at a centrally located plant for a premium quality. The concrete is then delivered to the
construction site in transit mixers and can be used straight away without any further treatment. The
automatic plant monitors weigh-batching, water-cement ratio, dosage of admixture, moisture
content, with precision to produce quality concrete.
All ingredients used for the preparation of ready mix concrete are thoroughly tested for their
quality and physical properties in a well equipped laboratory attached to the plant for conformity
to relevant international standard codes. The moisture probe determines the water content in the
sand and aggregates. This accordingly helps in fixing the proportion of water to be added for the
preparation of the mix. Trial mixes are carried out and tested to ensure that each and every batch
of concrete coming out of the plant meets various mix designs as per the client’s requirement with
different grades of concrete.
Advantages of ready-mix concrete
Following are the advantages of ready-mix concrete:
1. Ready Mix Concrete (RMC) allows speedy construction through programmed delivery at
site, mechanized operation with consequent economy.
2. RMC reduces the labour cost and site supervising cost.
3. RMC comes with consistency in quality through accurate & computerized control of sand
aggregates and water as per mix designs.
4. Production of RMC helps in minimizing cement wastage due to bulk handling.
5. Production of RMC is relatively pollution free.
6. Reduced project time resulting in savings in all aspects.
7. Proper control and economy in use of raw material resulting in saving of natural resources.
Disadvantages of ready-mix concrete
Following are the disadvantages of ready-mix concrete:

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1. The materials are batched at a central plant, and the mixing begins at that very plant. So
the travelling time from the plant to the site is critical over longer distances. Some sites are
just too far away, which can risk that ready mix concrete may become unusable due to
setting.
2. It will generate additional road traffic. Generally, Ready Mix Trucks are large in size and
may cover lot of area in the road blocking other traffic. Furthermore, access roads and site
access have to be able to carry the greater weight of the ready-mix truck plus load. (Green
concrete is approx. 2.5 tonne per m³.) This problem can be overcome by utilizing so-called
‘mini mix’ companies which use smaller 4m³ capacity mixers able to reach more-restricted
sites.
3. Concrete’s limited time span between mixing and curing means that ready-mix should be
placed within 210 minutes of batching at the plant. Modern admixtures can modify that
time span precisely, however, the amount and type of admixture added to the mix is very
important.
Volumetric mobile mixer
Volumetric mobile mixer can provide a good alternative to ready-mix concrete. This is a hybrid
approach between ready-mix concrete and traditional on-site mixing. The volumetric mobile mixer
is a truck that contains concrete ingredient materials and water to be mixed on the truck at the job
site to make and deliver concrete according to the amount needed. The on-truck mixing at the job
site eliminates the problems of ready-mix concrete such as delays that can cause the pre-mixed
concrete to become unusable.
Waterproofing concrete

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For certain types of works like water storage tanks, reservoirs, basement walls, roofs, swimming
pools, sewage units, etc. the impermeability of concrete is absolutely essential. In general, it can
be stated that if concrete is made dense and free from cracks, it is watertight. The dense concrete
can be obtained by closely adhering the following essentials:
1. Using a hight class Portland cement of guaranteed quality.
2. Taking extreme care to adopt correct grading and proportioning of the sand, aggregate and
cement.
3. Using clean and non-porous aggregate.
4. Mixing thoroughly to the right consistency using the right amount of water.
5. Placing, tamping and curing carefully.
6. Making use of suitable water-proofing compound.
The cement concrete to a certain extent may be made impermeable to the water by using
hydrophobic cement. All the flat roofs in the modern age are generally constructed of R.C.C. It
becomes necessary to give some treatment of waterproofing to such roofs.
Methods of waterproofing concrete
Following are the four methods adopted for waterproofing of R.C.C. flat roofs:
1. Finishing
2. Bedding concrete and flooring
3. Mastic asphalt and jute cloth
4. Use of water-proofing compounds
Finishing
For ordinary buildings of cheap construction, the finishing of roof surface is done at the time of
laying cement concrete. The finishing of flat roof is carried out in cement mortar of proportion 1:4
i.e. one part of cement to four parts of sand by volume.
Bedding concrete and flooring
In this method, the surface of R.C.C. slab is kept rough and on this surface, a layer of concrete is
laid. The concrete may be brickbats lime concrete (1:2:4) or brickbats cement concrete (1:8:14).
The thickness of the concrete layer is about 100mm. The surface of the bedding concrete is
provided by suitable flooring such as tiles, terrazzo, Indian patent stone, etc. A convex joint is
provided at the junction of parapet wall and roof.
Mastic asphalt and jute cloth
In this method, a layer of hot mastic asphalt is laid on the roof surface. The jute cloth is spread
over this layer. Then one more layer of mastic asphalt is applied so that the jute cloth is sandwiched
between the two layers of mastic asphalt. The sand is then sprinkled over the entire surface of roof.
For better grip, the lead sheets are inserted at the junction of parapet wall and roof.

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Uses of waterproofing compounds
Some of the waterproofing compounds like Pudlo, Impermo, etc. are available in the market and
when such a compound is added to the cement during construction, it prevents seepage, leakage
and damp caused by the capillary absorption of the moisture in cement, mortar and concrete. The
quantity of water-proofing compound to be added is also very small, say 2% and thus a bag of
cement will require only about 10N of such compound.
The water-proof compounds are available in the powder form and they are to be mixed thoroughly
with cement by hand before the cement is mixed with the aggregate.
Advantages of waterproofing concrete
The advantages claimed by using a waterproofing compound of good quality are as follows:
1. It corrects a badly proportioned concrete mixture.
2. It cures immature green concrete.
3. It makes good concrete from the poor materials.
4. It permits less rigid supervision of the workmanship.
Lightweight concrete
The bulk density of ordinary concrete is about 23 kN/m3
. The concrete having bulk density
between 5 to 18 kN/m3
is known as lightweight concrete and it is prepared from the following
materials:

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1. Binding material: The ordinary Portland cement and its varieties can be used as binding
material. If local binding material such as lime-slag, lime-cinder, etc. is available, the same
can also be adopted as the binding material.
2. Aggregates: For lightweight concrete, the loose porous materials are used as the
aggregates. The natural porous aggregates can be obtained by crushing lightweight rocks.
The artificial porous aggregates can be obtained from industrial wastes.
3. Steel: The lightweight concrete is highly porous and hence it leads to the corrosion of
reinforcement, if not properly protected. Hence, the lightweight concrete should be made
adequately dense when used for R.C.C. work. Sometimes, the reinforcement is coated with
anti-corrosive compounds, when lightweight concrete is adopted.
4. Water: It is necessary to use pure drinking water to prepare lightweight concrete. The
strength of lightweight concrete mainly depends on the amount of water in mix. The water-
cement ratio for achieving optimum strength of lightweight concrete should be carefully
worked out. As water content reaches to its optimum value, there is corresponding increase
in the strength of lightweight concrete.
Advantages of lightweight concrete
Following are the advantages of lightweight concrete:
1. The local industrial waste, if found suitable for lightweight concrete, can be economically
utilized.
2. The reduction in weight of concrete helps easy removal, transport and erection of precast
products.
3. The use of lightweight concrete results in the reduction of cost to the extent of about 30 to
40 percent.
4. The lightweight concrete doesn’t present special problems with respect to freezing and
thawing. It is due to the fact that the larger pores in aggregate are unlikely to become
saturated, provided the cement paste is protected by air entrainment.
5. The lightweight concrete has comparatively less tendency to spall. Hence, its fire resistance
is greater as compared to the ordinary concrete.
6. The lightweight concrete has generally a lower thermal expansion than ordinary concrete.
7. The sound absorption of lightweight concrete is good because of the fact that the air-borne
sound energy is converted into heat in the minute channels of the concrete. The sound
absorption coefficient of the lightweight concrete is nearly twice than that of the ordinary
concrete.
Disadvantages of lightweight concrete
The only drawback of lightweight concrete is that the depth of carbonation i.e. the depth within
which corrosion can occur under suitable conditions is nearly twice than that of normal concrete.
Hence, special care will have to be taken to provide sufficient cover to the reinforcement of the
lightweight structures to grant protection against corrosion.
Types of Foundation

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Before moving into types of foundation, let’s learn what is foundation or footing. Most of the
structure consist of two parts, one above the ground which is known as super structure and the
other sub-structure of the foundation which lies below the ground level. Foundation (aka footing)
is defined as that part of the structure that connects and transmits the load from the structure to the
ground soil. The solid ground on which the foundation rests is termed as the foundation bed. The
foundation transmits the load of the structure and it’s self-weight to the soil such that the ultimate
bearing capacity of the soil is not exceeded (the shear failure is not allowable) and the settlement
is tolerable.
Every structures are provide with foundation at the base to fulfill the following objectives and
purposes:
 To distribute the load of the structure over a large bearing area.
 To load the bearing surface at uniform rate so as to avoid unequal settlement.
 To prevent the lateral movement of the supporting material.
 To increase the stability of the structure as a whole.
Contents:
Shallow Foundation
 Wall Footing
 Isolated column/Column Footing
 Combined Footing
 Cantilever (Strap) Footing
 Mat (Raft) Foundation

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Deep Foundation
 Pile Foundation
 Pier Foundation
 Well (Caissons) Foundation
Factors affecting the selection of Foundation
Foundation are classified on the basis of load transmission to the ground into two sub-categories
i.e. shallow foundation and deep foundation.
Shallow Foundation
Shallow foundation are those foundations in which the depth at which the foundation is placed is
less than the width of the foundation (D < B). Shallow foundations are generally termed as spread
footing as they transmit the load of the super structure laterally into the ground.
Classification of Shallow Foundation:
On the basis of design, the shallow foundation are classified as:
 Wall Footing
 Isolated column or Column Footing
 Combined Footing
 Cantilever (Strap) Footing
 Mat (Raft) Foundation
Wall Footing
This type of foundation runs continuous along the direction of the wall and helps to transmit the
load of the wall into the ground. Wall footing are suitable where loads to be transmitted are small
and are economical in dense sands and gravels. In this type of foundation the width is 2-3 times
the width of the wall at ground level. Wall footing may be constructed through stone, brick, plain
or reinforced cement concrete.
Column Footing
Column footing are suitable and economical for the depth greater than 1.5m. In this type of
foundation the base of the column is enlarged. Column footing is in the form of flat slab and may
be constructed through plain or reinforced concrete.
Combined Footing
Combined footings are those foundations that are made common for two or more columns in a
row. It is used when the footing for a column may extend beyond the property line. It is also

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suitable when the two columns are closely spaced and the soil on which the structure resist is of
low bearing capacity. It may be rectangular or trapezoidal in shape.
Strap Footing
When an edge footing cannot be extended beyond the property line the edge footing is linked up
with the other interior footing by means of a strap beam. Such footings are called as strap footing.
It is also know as cantilever footing.
Mat Foundation
A mat foundation is a combined footing which covers the entire area beneath of a structure and
supports all the walls and columns. It is also known as raft foundation. Mat foundation is applicable
when:
 Allowable bearing pressure is low.
 The structure is heavy.
 The site is with highly compressible layer.
The mat foundation can be further classified into following types:
 Flat slab type.
 Flat Slab thickened under column.
 Two way beam and slab type.
 Flat slab with pedestals.
 Rigid frame mat.
 Piled mat.
Deep Foundation
Deep Foundation are those foundations in which the depth of the foundation is greater than its
width (D>B). The D/B ratio is usually 4-5 for deep foundation. Unlike shallow foundation, the
deep foundation transmits the load of the superstructure vertically to the rock strata lying deep.
Deep foundations are used when the shallow foundation cannot support the load of the structure.
Classification of Deep Foundation
The mat foundation can be further classified into following types:
 Pile Foundation
 Pier Foundation
 Well (Caissons) Foundation
Pile Foundation
Pile is a slender member with small area of cross-section relative to its length. They can transfer
load either by friction or by bearing. Pile foundation are used when:

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 The load is to be transferred to stronger or less compressible stratum, preferably rock.
 The granular soils need to be compacted.
 The horizontal and the inclined forces need to be carried from the bridge abutments and
the retaining walls.
Classification of Pile Foundation
The pile foundation can be further classified into following types on various basis such as function,
material, method of installation which are listed below:
Based on Function:
 Bearing piles
 Friction piles
 Combined piles (Both bearing and friction)
Based on Material:
 Timber piles
 Concrete piles
 Steel piles
Based on Method of Installation:
 Large displacement piles
 Small displacement piles
 Non-displacement piles
Pier Foundation
Pier foundation are underground cylindrical structural member that support heavier load of the
structure which shallow foundations cannot resist. Unlike pile foundation, pier foundation can only
transfer load by bearing. Pier foundation are shallower in depth than the pile foundation. Pier
foundation are used when:
 The top strata is a decomposed rock underlying as sound rock strata.
 The soil is a stiff clay that occurs large resistance for driving the bearing pile.
Well (Caissons) Foundation
The term caisson refers to box or a case. These are hollow inside and are usually constructed at
the site and sunk in place into a hard bearing strata. As they are expensive in construction, they are
usually restricted to major foundation works. Well foundation are suitable when the soil contains
large boulders obstructing the penetration during installation of pier or pile foundations. Caissons
are used for bridge piers, abutments in rivers and lakes and other shore protection works. They are
used to resist heavy vertical and horizontal loads and are used in the construction of large water
front structures as pump houses.