3. Timber
The wood suitable for
construction of
buildings or for other
engineering purposes
is called timber.
4. Uses and importance of
Timber
• Used as posts, beams, lintels, doors
and windows
• Used in floorings, roofing, ceilings
etc.,
• Used in rafters , purlins, trusses etc.,
• Used for interior decoration
purposes
• Used for making furniture, sport
goods, railway sleepers etc.,
5. TYPES
There are two types of timber:
• Hardwood
- Deciduous & having large leaves
- Eg., Teak, sal, Shisham
8. Requirements
• Durable and effective.
• Able to penetrate from inside.
• Should not adversely affect timber.
• Should not emit any offensive smell.
• Fire-proof.
• Poisonous for fungus, white ants and other insects.
• Cheap.
10. Importance of Sand
• Sand is an extremely needful material for the
construction but this important material must be
purchased with all care and vigilance. Sand which is
used in the construction purpose must be clean, free
from waste stones and impurities. It is important to
know what type of sand is beneficial for construction
purpose as sand is also classified into three different
forms that make it suitable for specific type of
construction.
11. • Should not contain impurities like Silt, Clay and salts.
These impurities can affect physical and chemical
properties.
• Free from organic matter.
• Coarse and well graded angular grains in suitable
proportions.
• Grains should be hard, strong and durable.
• Free from hygroscopic moisture.
12. Classification of sand
Sand is classified as:
• Fine Sand (0.075 to 0.425 mm),
• Medium Sand (0.425 to 2 mm)
• Coarse Sand (2.0 to4.75 mm).
However this classification of sand is further
has types of sand in particular and on that basis
only they are being incorporated in the
construction
13. Pit Sand
(Coarse sand)
• This type of coarse sand is procured from deep pits of
abundant supply and it is generally in red-orange color.
The coarse grain is sharp, angular and certainly free
from salts etc which is mostly employed in concreting.
14. Sea Sand
• The name suggest, sea sand is taken from seas shores and it is
generally in distinct brown color with fine circular grains. Sea
sand is avoided for the purpose construction of concrete
structure and in engineering techniques because it contains salt
which tends to absorb moisture from atmosphere and brings
dampness. Eventually cement also loses its action when mixed
with sea sand that is why it is only used for the local purpose
instead of structural construction.
15. River Sand
• River sand is procured from river streams and banks and is fine
in quality unlike pit sand. This type of sand has rounded grains
generally in white-grey color. River sand has many uses in the
construction purpose such as plastering.
16. General Requirements
• All the sand particles should have higher crushing strength.
• The surface texture of the particles should be smooth.
• The edges of the particles should be grounded.
• The ratio of fines below 600 microns in sand should not be less
than 30%.
• There should not be any organic impurities
• Silt in sand should not be more than 2%, for crushed sand.
• In manufactured sand the permissible limit of fines below 75
microns shall not exceed 15%
18. Aggregates
Definition - Aggregate is a type of material used in
construction, including sand, gravel, crushed stones
etc.
19. Requirements of Good
Aggregates
• It should be chemically inactive
• It should be sufficiently strong
• It should be hard enough
• It should be durable
• It should have rough surface
• It should be of proper shape
• It should have limited pores
22. According to Formation -
1. Natural Aggregates
Natural aggregates consists
of rock fragments that are
used in their natural state,
or are used after
mechanical processing
such as crushing, washing,
and sizing.
23. 2. Artificial Aggregates
For making special type
of concrete we should
make special type of
artificial aggregates. In
these aggregates most
are light weight
aggregates and heavy
weight aggregates.
24. According to Size -
1. Fine
Aggregates
“Fine aggregate” is
defined as material
that will pass a No. 4
sieve and will, for the
most part, be retained
on a No. 200 sieve.
Some types are sand,
stone dust, cinder,
surkhi.
25. 2. Coarse Aggregate
Coarse aggregate basic
material of the concrete.
Crushed stone or gravel
used in concrete are
called coarse aggregate
and it will not, pass
when it is dry through a
sieve with ¼-inch-
diameter. Some types are
stone ballast, gravel,
clinker etc.
26. Uses of Aggregates
• In Concrete making,
• In making Roads,
• For laying Railways,
27. Properties of Aggregates
Aggregates sizes
Aggregates shape
Aggregates surface
textures
Specific gravity of
aggregates
Water absorption and
surface moisture
28. Importance of Aggregates
• Aggregates are the literally the foundation of our economy and
society.
• It is used in greater quantities than any other natural
resources.
29. • It is used for building our basic needs like home, office,
buildings, bridges, roads, highway etc.
• Almost every field of job depends on aggregate industry.
• Economic growth depends on maintaining a competitive
supply of high quality aggregates at a reasonable cost and
close to market.
31. Definition
• Mortar is a workable paste used to bind building blocks such
as stones, bricks, and concrete masonry units together, fill and
seal the irregular gaps between them, and sometimes add
decorative colors or patterns in masonry walls. In its broadest
sense mortar includes pitch, asphalt, and soft mud or clay, such
as used between mud bricks. Mortar comes from
Latin mortarium meaning crushed.
32. Importance
• To bind together the bricks or stones properly so as to provide
strength to the structure.
• To form a homogenous mass of the structure so as to resist all the
loads coming over it without disintegration.
• To provide a weather resisting i.e., a durable layer between the
different courses of masonry in the structure.
• To hold coarse aggregate together in any concrete so as to form a
solid mass. The mortar used in a concrete is termed as matrix.
• To do pointing and plastering to the structure. The mortar used for
plastering is known as plaster.
• To fill up empty joints in brick and stone masonry. The mortar used
for such purposes is a thin liquid mortar which is termed as grout and
the process is known as grouting.
33. Requirements
• good workability to ease laying work and improve quality of the
joints
• good water retentivity to prevent excessive suction of water by
bricks that have high initial rate of absorption and retain
sufficient water required for hydration of cement
• development of suitable early and final strength
• offers water-tightness and durability to a wall
• good adhesion or bond for bricks
35. TYPES OF MORTAR AND ITS USES:
Cement mortar:
•The paste is prepared by mixing cement and sand in
suitable proportions in addition to water.
•The general proportion is 1 part of cement to 2-8 parts
clean sand.
•These mortars must be use within half an hour, i.e.; before
initial setting time of the cement.
•USE-This type is used for all engineering works where high
strength is desired such as load bearing walls, deep
foundations, flooring etc.
36. Lime mortar:
•The paste is prepared by mixing lime and sand or surkhi in
suitable proportions in addition to water.
•If surkhi is to be added in lime mortar the equal
proportions of sand and surkhi should be mixed with lime.
•These mortars are inferior to cement mortars in strength
as well as water tightness.
•These mortars should not be used for underground works
as they set in the presence of carbon dioxide and break up
in damp conditions.
•USE- This type is used for construction work above ground
level i.e. exposed positions.
37. Light weight mortar:
•The paste is prepared by mixing wood powder,
wood sawing or saw dust with cement or lime
mortar.
•In such mortars fibers of jute coir or asbestos fibers
can also be used.
•USE- These are generally used as fiber plasters in
sound and heat proof construction.
38. Fire resistant mortar:
•The paste is prepared by mixing aluminous
cement and finely crushed fire bricks in suitable
proportions in addition to water.
•The usual proportion are 1 part aluminous
cement to 2 parts of finely crushed fire bricks.
•USE-These are generally used for lining furnaces,
ovens and fire places with fire bricks.
39. Mud mortar:
•The paste is prepared by mixing suitable clayey
soil with water.
•The soil which is used for preparing mud mortar
should be free from grass, pebbles etc.
•These are the cheapest mortars but weakest in
strength.
•USE- These mortars are used for brickwork of
ordinary buildings and for plastering walls in rural
areas.
42. Definition
• It is a mixture of portland cement, water, aggregates, and in
some cases, admixtures.
• The cement and water form a paste that hardens and bonds the
aggregates together.
• Concrete is often looked upon as “man made rock”.
Portland Cement
43. Properties
• Concrete has strength, durability, versatility, and economy.
• It can be placed or molded into virtually any shape and
reproduce any surface texture.
• Concrete is a versatile construction material, adaptable to a
wide variety of agricultural and residential uses.
• The elasticity of concrete is relatively constant at low stress
levels but starts decreasing at higher stress levels as matrix
cracking develops.
• Concrete has a very low coefficient of thermal expansion, and
as it matures concrete shrinks.
44. Importance
• With proper materials and techniques, concrete can withstand
many acids, silage, milk, manure, fertilizers, water, fire, and
abrasion.
• Concrete can be finished to produce surfaces ranging from
glass-smooth to coarsely textured, and it can be colored with
pigments or painted.
• Concrete has substantial strength in compression, but is weak in
tension.
• Most structural uses, such as beams, slats, and manure tank
lids, involve reinforced concrete, which depends on concrete's
strength in compression and steel's strength in tension.
45. Requirements of a good
concrete
• The fundamental requirements of hardened concrete are
strength, durability and economy. Fresh concrete must be
workable, that is, it must be of such a consistency and physical
make-up that it can be readily placed in the form without
segregation of the materials and without requiring an excessive
amountof spading to completely fill the form. Uniformity in
both the fresh and hardened concrete is necessary to secure
economy of materials, to facilitate handling and placing and to
obtain uniformity in the completed structure. It is particularly
important where water tightness is required.
46. Uses
Concrete has many applications and is used to make:
• pavements,
• pipes,
• structures,
• foundations,
• roads,
• bridges/overpasses,
• walls and
• footings for gates.
47. Types
There are various types of
concrete for different
applications that are created by
changing the proportions of the
main ingredients.
The mix design depends on the
type of structure being built, how
the concrete will be mixed and
delivered, and how it will be
placed to form the structure.